Apache Wicket 10.10.0, 10.11.0 and 9.24.0 do not set the Content-Security-Policy headers on a page whose render request handler is wrapped in more than one IRequestHandlerDelegate. The framework unwraps only a single delegate level when deciding whether a request renders a page, so with a deeper chain, for example an application-provided delegating request mapper combined with CryptoMapper, the page is served without any CSP header even though CSP is enabled, and no error or warning is raised. The nonce-based protection Wicket applies to inline scripts and styles, together with any other CSP directives configured by the application, is thereby lost for those pages, exposing them to content injection the policy was meant to prevent. Applications on stock Wicket that do not wrap request handlers themselves are not affected. Versions before 10.10.0 and 9.24.0 handled nested delegates correctly. Users are recommended to upgrade to version 10.12.0 or 9.25.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.html.link.ExternalLink builds a JavaScript click handler and writes it into the tag's onclick attribute whenever the markup tag the component is bound to is not an a, link or area element. The URL held in the component's model is concatenated into a single-quoted JavaScript string literal in that handler without being escaped for that context. The same happens on the neighbouring branch, taken when popup settings are attached, where the value is concatenated into the window.open() call built by org.apache.wicket.markup.html.link.PopupSettings#getPopupJavaScript(). The only escaping applied is the markup escaping that every attribute value receives as the tag is written, which replaces an apostrophe with a character reference. A browser decodes character references in an attribute value before it compiles the event handler, so the apostrophe is restored, closes the string literal, and the rest of the model value is executed as script in the application's origin.
An application is affected where it binds an ExternalLink to a markup tag that is not an anchor, such as a button or a span, and the URL in the model holds data an attacker can influence, which is the ordinary use of the component rather than a misuse of it. Nothing runs until a user activates the element.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version.
Users are recommended to upgrade to version 8.20.0, which fixes the issue.
Incorrect behavior order in Apache Wicket: a file path is validated before the framework appends the attributes that complete it.
org.apache.wicket.request.resource.PackageResource asks the configured package resource guard about a path built from the scope class' package and the file name in the request URL, and then hands that same path to the resource stream locator together with a style, a variation and a locale. Those three attributes are decoded from the name of the first query parameter and never appear in the string the guard was given. org.apache.wicket.core.util.resource.locator.ResourceNameIterator appends them to that path, each preceded by an underscore, in the order variation, style, locale, before the file extension, so the file that is opened is not the file the guard approved.
org.apache.wicket.markup.html.PackageResourceGuard decides whether an HTML file is a component's markup template by looking for a class file of the same name beside it, stripping one underscore-delimited suffix at a time as it goes. HTML is on the default allow list, so that check is the only thing separating a static HTML file, which may be served, from a markup template, which may not. Asked about the name of a template, the guard refuses it correctly. Asked about a shorter name for which no class exists, it accepts, and a style supplied in the URL then completes that name into the markup template of a component class, which is written to the response.
An application is affected if the simple name of any of its component classes contains an underscore and no shorter part of that name is itself a class, such as Reportv2 or WizardStep1; an application with no such class name is not affected. No unusual deployment, packaging or configuration is required, and running in deployment rather than development mode does not prevent it. Java naming conventions discourage underscores in class names and no module Wicket ships has one, so no framework markup is exposed; what an application exposes this way is its own. A component whose class name has no underscore is not reachable, and neither is its localized or styled markup, because the guard finds the class file under the base name and refuses the request. The attributes cannot change the file extension and cannot leave the component's package, so nothing beyond HTML files in that package is reachable. Access is read-only, and what is disclosed is developer-authored template content: component structure, developer comments, markup that is rendered only under some conditions, inline script, and the endpoints a template names. No user data, credential or session material is reachable this way. An attacker has to name a class in the target package and the component itself, and Wicket writes fully qualified class names into the URL of every package resource it renders.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Files accessible to external parties in Apache Wicket.
org.apache.wicket.markup.html.PackageResourceGuard decides whether a file on the classpath may be streamed to a client as a package resource. HTML is on the default allow list, so the only thing that separates a static HTML file, which may be served, from a component's markup template, which may not, is a check for a class file of the same name beside it. That check calls getResource() on the class loader that loaded wicket-core. The resource itself is reached through different class loaders: the scope class is resolved through the application's IClassResolver, which uses the thread context class loader, and org.apache.wicket.core.util.resource.ClassPathResourceFinder#find() then tries the scope class' own loader, the context class loader, and the wicket-core loader last.
Where wicket-core is loaded by a class loader that cannot see the application's classes, the check finds no class file, concludes the file is not a component markup template, and serves it. A request for the package resource URL of a component class then returns that component's markup template with status 200. What is disclosed is developer-authored template content: component structure, developer comments, markup that is rendered only under some conditions, inline script, and the endpoints a template names. Access is read-only, and no user data, credential or session material is reachable this way.
Such a deployment is rare. The ordinary packaging, a web archive with wicket-core in WEB-INF/lib, puts the framework and the application in one class loader, so the check finds the class file and the template is refused; those deployments are not affected. The exposure is confined to deployments that give wicket-core a class loader which cannot see the application's component classes: wicket-core placed in a servlet container's shared library directory, in an enterprise archive library directory with the application in the web archive, as an application server global module, or as an OSGi bundle, where wicket-core's bundle cannot resolve a class held by an application bundle. Markup shipped by Wicket's own modules, and by any other code sharing a class loader with wicket-core, remains protected. An attacker has to name a component class, and Wicket writes fully qualified class names into the URL of every package resource it renders.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Allocation of resources without limits or throttling in Apache Wicket.
org.apache.wicket.markup.html.form.upload.resource.AbstractFileUploadResource is the server side of the form-less upload offered by FileUploadToResourceField, which posts the selected files to a separately mounted resource rather than through a Form. The resource is an application-wide singleton with no component to consult, so newResourceResponse() takes the three limits that bound the upload - the total request size, the maximum size of a single part and the maximum number of parts - from the request parameters maxSize, fileMaxSize and fileCountMax, and hands them to the multipart parser as they arrive. Nothing binds those numbers to the field that is supposed to be uploading. A request naming a very large maxSize is therefore parsed with no effective ceiling on the total size, and omitting fileMaxSize and fileCountMax leaves the per-part and part-count limits unset as well. The values the application configured through FileUploadToResourceField#setMaxSize(), #setFileMaxSize() and #setFileCountMax() are consulted only when the client omits the corresponding parameter, so against a client that supplies one they have no effect at all.
Parts above the parser's in-memory threshold are spooled to the container's temporary directory, and the file parts are then copied into the folder the application's IUploadsFileManager owns, under a sub-folder the request names, where they remain. A part that is not a file is read into the heap in full while the request is parsed. One request, repeatable, can therefore consume as much disk or as much heap as the client chooses to send. The resource carries no authorization annotation and the default authorization strategy permits every resource request, so unless the application authorizes the resource itself the request needs no authentication, no session, no prior page view and no user interaction.
An application is affected where it uses FileUploadToResourceField, or mounts FileUploadResourceReference itself. This is not the ordinary upload path: the resource is a singleton that has to be created and mounted deliberately. An application that configures no upload limit at all loses nothing, because Wicket applies no total-size limit of its own by default; what the defect removes is a limit the application set. Uploads through Form with FileUploadField, and through AjaxFileDropBehavior, are not affected, because both read their limits from the component rather than from the request. The upload resource does not exist in the 8.x line.
This issue affects Apache Wicket: from 9.14.0 through 9.24.0, from 10.0.0 through 10.9.1. Users are recommended to upgrade to version 9.25.0 or 10.12.0, which fix the issue.
Memory allocation with an excessive size value in Apache Wicket.
org.apache.wicket.markup.html.form.upload.resource.FileUploadToResourceField uploads files to a separately mounted resource rather than through a form, and is told the outcome afterwards over its own Ajax callback. That callback reads the request parameter filesInfo, a JSON array carrying a client file name, a size and a content type for each file, and turns it into the list of FileUploadToResourceField.UploadInfo that onUploadSuccess() receives. Nothing binds that JSON to an upload the resource performed and nothing re-derives it from the stored files, so the number of entries and every value in them are whatever the request supplied. The callback URL is rendered into the page, no prior upload is required, and both GET and POST reach it, so any client that can load the page can have the component report files that were never uploaded, without authenticating beyond whatever the page itself requires and without any user interaction.
UploadInfo#get(), which the class offers as the way to obtain the bytes of an upload, allocates a byte array from UploadInfo#getSize() before it opens the file. The array is therefore sized by the number the request supplied, and the allocation happens even for a file that was never stored. One small request can cost the server close to two gigabytes of heap, and the request is trivially repeatable, so a few of them exhaust the heap for every request the Java virtual machine is serving. A size that the conversion to int turns negative instead throws NegativeArraySizeException, which the exception handler inside that method does not cover, so it escapes into the application.
An application is affected where it uses FileUploadToResourceField, which is not the ordinary upload path through FileUploadField and Form and has to be extended and mounted deliberately. The allocation additionally requires the application to call UploadInfo#get() rather than reading UploadInfo#getFile() itself. Where the application denies the ENABLE action on the field through its authorization strategy, the callback is refused like any other listener. The 8.x line does not contain this component and is not affected.
This issue affects Apache Wicket: from 9.14.0 through 9.24.0, from 10.0.0 through 10.11.0. Users are recommended to upgrade to version 9.25.0 or 10.12.0, which fix the issue.
Improper encoding or escaping of output in Apache Wicket.
org.apache.wicket.core.util.string.JavaScriptUtils#escapeQuotes() replaces each single quote in its input with a backslash and a single quote, and each double quote with a backslash and a double quote, so that the value can be placed inside a JavaScript string literal. It does not escape the backslash, which is the character that has to be escaped, and escaped first, for the rest of that escaping to hold. A value that already holds a backslash immediately before a quote therefore ends up with two backslashes in front of that quote: the first escapes the second, the quote itself is left unescaped, and it closes the literal. Whatever the value carries after that point is no longer text but JavaScript, and it runs in the application's origin and in the session of the user looking at the page. The method is public, is not deprecated, and its documentation states that its result can be part of a JavaScript call such as an alert; the only limitation it notes concerns JSON values, which need different escaping.
An application is affected wherever it calls the method itself and places the result inside a JavaScript string literal, from its own code or from a component of its own or of a third party, and the value it escapes holds data an attacker can influence. There is no further condition, and no component of Wicket has to be involved: the application is using the method for what its documentation offers, and the method does not deliver it.
Two components shipped with Wicket Extensions pass a value through the method. org.apache.wicket.extensions.ajax.markup.html.AjaxEditableLabel writes the editor's first error feedback message into a single-quoted JavaScript string literal in the Ajax response, so an application is affected through that component where the message shown for a failed edit holds data an attacker can influence, whether that is the submitted value itself or another variable the application sets on the validation error. A validation message can carry the submitted value, because input is a message variable that every form component supplies for its own validation errors, and the documentation shows overriding a validator's message to include it; none of the message bundles shipped with Wicket interpolates it, so an application that has not written such a message is not affected through this component. org.apache.wicket.extensions.ajax.markup.html.repeater.AjaxListPanel passes the serialized markup tag of an appended component through the method and is not affected: the tag comes from the panel's own markup file, and a quote in any of its attribute values, the component's markup id included, is written as a character reference by the tag serialization and cannot close the literal.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version.
Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.extensions.markup.html.basic.SmartLinkLabel and org.apache.wicket.extensions.markup.html.basic.SmartLinkMultiLineLabel display a text value and turn any URL they find in it into a hyperlink. Both escape the model value and then hand the escaped text to org.apache.wicket.extensions.markup.html.basic.DefaultLinkParser, which searches it for anything of the form scheme://rest and wraps each match in an anchor whose href is the matched text, copied in as it is. The pattern accepts any scheme, and there is no list of permitted schemes anywhere on the path. A text value naming a scheme that executes script therefore becomes an anchor that executes it, in the application's origin and in the reader's own session, when the reader clicks the link. Rendering the page is not enough on its own; the link has to be activated. Escaping does not prevent this and is not the issue: the characters the payload needs are all valid in a URL and are ones that org.apache.wicket.util.string.Strings#escapeMarkup() leaves alone, and the value ends up in a URL rather than in element text, which is a context that escaping model data does not make safe.
An application is affected where it renders text it received through either of these two components. That is what they are for: they exist to linkify email addresses and web URLs found in the data an application is displaying, so untrusted input is the purpose of the feature rather than a misuse of it, and no unusual configuration is involved. No other component uses this parser, and an application that uses neither SmartLinkLabel nor SmartLinkMultiLineLabel is not affected.
On 9.x and 10.x the Content-Security-Policy Wicket sends by default admits script only from a source carrying a per-response nonce, and a URL whose scheme executes script cannot carry one, so that default policy stops the script from running. This is a property of the default policy and not of these components. An application that has weakened or disabled its Content-Security-Policy, for this or for any unrelated reason, is affected in full. Wicket 8.x has no Content-Security-Policy support at all and is affected as it stands.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.ajax.AjaxNewWindowNotifyingBehavior notices that a page instance has been opened in a second browser window or tab. It asks the browser for the value of window.name, which reaches the server as the request parameter windowName, and remembers what the browser reported in a field of the behaviour. That field is part of the page's serialized state, so the remembered value stays in the page store for as long as the page instance does.
On every later render of that page instance the behaviour builds the precondition of its Ajax call by substituting the remembered value into a single-quoted JavaScript string literal, and Wicket writes that precondition into the page as raw JavaScript, because the precondition of an Ajax call listener is script supplied by the caller and is emitted without quoting or escaping. Nothing on that path escapes the value. The window name is client-supplied and Wicket applies no validation to it, so a remembered name containing a single quote ends the literal and the rest of it runs as script in the application's origin, every time that page instance is rendered.
An application is affected only where it has explicitly added AjaxNewWindowNotifyingBehavior to a component. No part of the framework installs the behaviour, so an application that does not use it is not affected. The name the behaviour generates for itself, when the browser reports no name at all, is a random UUID and is not client-supplied.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0.
Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Incorrect order of security checks in Apache Wicket.
org.apache.wicket.protocol.http.ResourceIsolationRequestCycleListener obtains the page a request targets before it consults its resource isolation policies, because those policies are passed that page. Obtaining the page instantiates it, and instantiating a page runs the configured org.apache.wicket.authorization.IAuthorizationStrategy. An application that refuses an unauthenticated visitor by throwing org.apache.wicket.RestartResponseAtInterceptPageException therefore throws it from inside the isolation listener, before any policy has run. That exception replaces the request handler, so the policies are never consulted and a request that came from another origin is not refused.
The exception's constructor stores the URL of the request it interrupted, so that Component#continueToOriginalDestination() can resume it once the visitor has signed in. The stored URL is the one the policies would have refused. On sign in Wicket redirects to it, and that redirect is same-origin, so the policies allow it and the listener runs in the newly authenticated session. The whole URL is stored, its query string included, so an ordinary org.apache.wicket.markup.html.form.Form is resumed with the field values the original request carried in its query string and Form#onSubmit() runs with values another origin chose. A form POST is not needed for this; a plain top-level navigation carries them.
An application is affected where it registers ResourceIsolationRequestCycleListener, which is opt-in and is not registered by default, and where it refuses unauthorized access with RestartResponseAtInterceptPageException followed by continueToOriginalDestination(). No application override is involved on that path: IAuthorizationStrategy#isInstantiationAuthorized() documents throwing that exception, org.apache.wicket.authroles.authentication.AuthenticatedWebApplication throws it and org.apache.wicket.authroles.authentication.panel.UsernamePasswordPanel continues to the original destination, and org.apache.wicket.authorization.strategies.page.SimplePageAuthorizationStrategy in wicket-core installs the same pattern. A visitor who is already signed in is not affected, because no interception occurs. Request-body parameters stored alongside the intercepted URL are not applied to the resumed form: the resumption is a redirect, so the resumed request is a GET, and form components read their values from the query string on a GET.
As a workaround, refuse unauthorized access with org.apache.wicket.RestartResponseException instead, which does not store the original destination; visitors are then not returned to the page they asked for after signing in.
This issue affects Apache Wicket: from 9.1.0 through 9.24.0, from 10.0.0 through 10.11.0.
Releases before 9.1.0, which is every 8.x release and 9.0.0, are not affected, because the resource isolation this issue concerns was introduced in 9.1.0. They are not protected either. Their only cross-origin defence is org.apache.wicket.protocol.http.CsrfPreventionRequestCycleListener, which works out where a request came from by reading its Origin header and falling back to its Referer header. Neither header need arrive: a browser does not send Origin on the plain GET a link uses, and the document on the other origin decides through its own referrer policy whether a Referer reaches the application at all. That mechanism therefore never made the guarantee the Fetch Metadata based policy makes, and on those releases a listener invocation from another origin is not reliably refused in the first place. Anyone on a release before 9.1.0 who wants this protection should upgrade to 9.x or 10.x and register ResourceIsolationRequestCycleListener.
Users are recommended to upgrade to version 9.25.0 or 10.12.0, which fix the issue.
Session fixation in Apache Wicket.
org.apache.wicket.authroles.authentication.AuthenticatedWebSession is the authentication base class of Wicket's role-based security module, and its signIn(String, String) method is the entry point through which an application authenticates a session. Renewing the container session id at that point is the standard defence against an attacker who has fixed a session id in a victim's browser, and Wicket provides that renewal as org.apache.wicket.Session#changeSessionId(), whose documentation directs callers to invoke it on login for exactly that reason.
AuthenticatedWebSession#signIn(String, String) calls it inside a guard that succeeds only on the first transition of the session's signed-in flag. The session id is therefore renewed when a session first signs in, and is not renewed when a session that is already signed in authenticates again. signIn(String, String) returns true either way, so neither the caller nor the application can tell that the renewal did not happen.
An application is affected where it authenticates through AuthenticatedWebSession, which AuthenticatedWebApplication requires and which the shipped UsernamePasswordPanel uses, and where a session that is already signed in can authenticate again: a step-up prompt before a sensitive action, an account switch, or simply a sign-in form that stays reachable once the user is signed in. Nothing in the module hides that form from a signed-in session. Reaching the defect also requires an attacker to place a session id of their choosing in the victim's browser. JSESSIONID is set by the servlet container rather than by Wicket, so that needs a position Wicket does not grant, such as control of a host under the same registrable domain or a container configured to carry the session id in the URL, and the planted session has to be one the attacker has already signed in on, because a session that is not yet signed in does have its id renewed by the victim's authentication. An authentication attempt that fails signs the session out and closes the window. Applications that renew the session id in their own code after a successful authentication are not affected.
As a workaround, renew the session id from the application's own code on every successful authentication, by calling Session#changeSessionId() at the end of the authenticate(String, String) implementation.
This issue affects Apache Wicket: from 8.18.0 through 8.19.0, from 9.23.0 through 9.24.0, from 10.9.0 through 10.11.0.
Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Missing authorization in Apache Wicket.
org.apache.wicket.authorization.IAuthorizationStrategy declares isResourceAuthorized(), and that method has a single enforcement point in the framework: org.apache.wicket.request.handler.resource.ResourceRequestHandler, the handler that serves a resource reached through a mounted or shared ResourceReference. Components that are handed an org.apache.wicket.request.resource.IResource instance instead call IResource#respond() themselves from their own request listener and never construct that handler. In wicket-core these are org.apache.wicket.markup.html.link.ResourceLink, org.apache.wicket.markup.html.image.Image and org.apache.wicket.markup.html.form.ImageButton; in wicket-extensions it is org.apache.wicket.extensions.ajax.AjaxDownloadBehavior. A resource restricted by a custom isResourceAuthorized() implementation, or by an @AuthorizeResource annotation from wicket-auth-roles, is therefore enforced when it is requested through its own resource URL and is not enforced when the same instance is served through the component that holds it.
Which of the two happens is decided by the constructor the application used, and not by anything the application can see in the rendered page. ResourceLink(String, ResourceReference) renders a resource URL and the request is authorized; ResourceLink(String, IResource) renders a component listener URL and it is not. Image, ImageButton and AjaxDownloadBehavior each offer the same pair of constructors and behave the same way. Image and ImageButton write that listener URL into the src attribute of the tag they render, so a browser requests it without any action by the user, and the resource an Image serves may also come from the component's model.
An application is affected where it restricts a resource through IAuthorizationStrategy#isResourceAuthorized() or an @AuthorizeResource annotation and then hands that same resource to one of those components as an IResource. An application that does not restrict resources at all is not affected, and neither is a resource that is only mounted or registered as a shared resource. The pattern does not have to be written by the application itself: org.apache.wicket.extensions.markup.html.repeater.data.table.export.ExportToolbar builds each of its export links from an IResource instance, so the exported contents of a data table are served without the resource check in any application that adds that toolbar.
As a workaround, register the resource in the application's shared resources and pass the resulting ResourceReference to the component instead of the IResource, so that the request is routed through the handler that consults the authorization strategy.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Missing authorization in Apache Wicket.
org.apache.wicket.core.request.handler.ListenerRequestHandler invokes an IRequestListener only when org.apache.wicket.Component#canCallListener() allows it, and that method is isEnabledInHierarchy() && isVisibleInHierarchy(). The visibility half reads a flag that carries the outcome of IAuthorizationStrategy#isActionAuthorized() for the Component.RENDER action, and that flag is written in one place only, Component#configure(), during the render phase. A listener URL built by a subclass of org.apache.wicket.core.request.mapper.AbstractBookmarkableMapper carries the page identifier and the component path in a single parameter, and the page identifier may be empty. When it is, a new page instance is constructed, PageProvider#wasExpired() is false because no identifier was supplied, and PageAndComponentProvider#getComponent() finds the component directly on the new instance, so neither a render pass nor Component#configure() runs before the listener is invoked. The flag therefore still holds its constructor default, the component counts as visible, and the listener of a component the authorization strategy denied RENDER for is executed. The same request also skips Component#onConfigure(), so visibility and enablement an application sets there are not applied either.
There are two ways to reach this, and neither requires anything but a request. On a page that is stateful, the caller omits the page identifier from a listener URL that would otherwise carry it. On a page that Wicket considers stateless, nothing has to be altered at all: Wicket itself writes listener URLs without a page identifier for such pages, and a component the strategy denies RENDER for is treated as stateless and therefore does not keep the page stateful, so denying RENDER can itself produce the page-id-less form. The second route has never been refused. The ENABLE decision of IAuthorizationStrategy is consulted on every invocation and still refuses, as does a request that supplies the real identifier of a page instance that has already been rendered; a component the application disabled in Component#onConfigure() is protected by neither, because that callback has not run.
An application is affected where it withholds an individual component from the caller, either by denying the RENDER action through IAuthorizationStrategy, including through the MetaDataRoleAuthorizationStrategy and AuthorizeAction facilities of wicket-auth-roles, or by setting the component's visibility or enabled flag in Component#onConfigure(), the callback Wicket's own documentation directs applications to use for both. The page carrying such a component has to be constructible from a bookmarkable or mounted URL, which requires a public constructor taking either no arguments or a PageParameters argument. Behaviours pass through the same gate, so an AJAX behaviour attached to such a component is equally exposed. Separately, and whether or not any component is withheld, a listener on a page Wicket considers stateful is invoked on an instance the request itself constructed, so it acts on models built from page parameters the caller supplied rather than on the state the application last rendered. Instantiation authorization is unaffected: IAuthorizationStrategy#isInstantiationAuthorized() is still consulted when the new page instance is created, so a guard placed on the page rather than on the individual component continues to hold.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Insufficient session expiration in Apache Wicket.
org.apache.wicket.protocol.ws.WebSocketSettings#newWebSocketRequest() wraps the WebSocket upgrade request in an org.apache.wicket.protocol.ws.api.ServletRequestCopy, which is kept for the life of the connection and used to build the request for every frame that arrives on it. Copying the request is deliberate and is documented as such, because the container recycles the upgrade request once the handshake is over. The container session is copied along with it, into an org.apache.wicket.protocol.ws.api.HttpSessionCopy holding the session attributes as they stood when the connection was opened. That second copy is not necessary, because a session, unlike a request, is not discarded at the end of a request. Every frame afterwards resolves its Wicket session through ISessionStore#lookup(), which reads it out of the copy, so the connection is detached from the live container session for as long as it stays open.
Ending the session through the container therefore does not end the connection. After an idle timeout, an HttpSession#invalidate() call made from a filter or from a security framework, a container-managed logout, or a session replacement, the connection goes on resolving the org.apache.wicket.Session instance that existed when it was opened, together with that session's attributes and, for applications built on wicket-auth-roles, the signed-in state held on that same instance, so an authorization decision taken inside a WebSocket callback is taken against an identity that has already been revoked. The copy is also what the connection writes through: a Session#invalidateNow() issued from inside a WebSocket callback invalidates the copy and leaves the container session valid, and session attributes set over the connection are written to the copy rather than to the session.
An application is affected where it uses Wicket's native WebSocket support on pages or shared resources that require an authenticated session, and where sessions are ended by the container rather than by Wicket. Session#invalidateNow(), and AuthenticatedWebSession#invalidate() and #signOut() which call it, remain effective for a WebSocketBehavior on a page: they clear the page manager, and the connection can then no longer resolve the page it was opened for. A WebSocketResource is not limited in that way, because a frame naming a resource is served against a throwaway page and never consults the page manager, so such a connection outlives Wicket's own sign-out as well. Some containers close WebSocket connections themselves when the HTTP session they were opened under is destroyed, in which case the connection ends regardless; that is a property of the container rather than of Wicket. Applications that do not use the native WebSocket support are not affected.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Older, unsupported releases from 6.0.0 onwards are also affected. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Missing authorization in Apache Wicket.
org.apache.wicket.protocol.ws.api.WebSocketBehavior, through which Wicket's native WebSocket support hands a message sent by the client to the application, calls its onMessage() callbacks without checking whether the client may invoke the component the behavior is attached to. Wicket opens a single WebSocket connection per page, and a message received on it is delivered to every WebSocketBehavior of that page. For an Ajax behavior Wicket makes this check before invoking it, through Behavior#canCallListener(Component), which refuses a component that is not visible or not enabled, including one for which the IAuthorizationStrategy denies the RENDER or ENABLE action. A WebSocketBehavior attached to such a component, or to a child of one, therefore receives the client's text and binary messages, together with a WebSocketRequestHandler that writes back to that client, where an Ajax behavior on the same component would be refused.
An application is affected where it attaches a WebSocketBehavior that overrides onMessage() to a component that it hides, disables, or restricts through its IAuthorizationStrategy, for example with MetaDataRoleAuthorizationStrategy or the AuthorizeAction annotation. The client needs a session of their own and a page of their own that contains such a component: messages are delivered only to pages in the page store of the client's own session, so this gives no access to another user's session, page or connection. Messages pushed by the server are not affected.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Older, unsupported releases from 6.0.0 onwards are also affected. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
On 1 November the Apache Wicket PMC published 19 security advisories. All of the issues are fixed in Apache Wicket 8.20.0, 9.25.0 and 10.12.0, for the release lines each one affects, and we recommend upgrading. 8.20.0 and 9.25.0 are the final releases of the 8.x and 9.x lines, which have now reached end of life, so if you are on 8.x or 9.x, please plan your move to Wicket 10 (LTS) or Wicket 11. Releases older than 8.x are no longer supported and do not get these fixes.
Apache Wicket: Native WebSocket: authorization strategy not applied to a shared WebSocketResource CVE-2026-82115 (MEDIUM): https://lists.apache.org/thread/0lj9og7vp22ps77nrwdj42f64cfb9g4c WebSocketMessageBroadcastHandler called WebSocketResource#onPayload() directly instead of going through ResourceRequestHandler, so IAuthorizationStrategy#isResourceAuthorized() and @AuthorizeResource were never consulted and any client with a session could drive the resource's callbacks. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Form: disabled or invisible submitting component invoked on a plain submission CVE-2026-82557 (MEDIUM): https://lists.apache.org/thread/lz4jot6f9ycxfjyhmlr2b4ssynmgpy92 Form#onRequest() handed the submitter it resolved from the request straight to onFormSubmitted(), skipping the visible-and-enabled check, so a request naming a withheld Button or SubmitLink reached its onSubmit(), including one denied by the authorization strategy. Fixed in: 10.12.0 Affected: from 10.3.0 before 10.12.0
Apache Wicket: Native WebSocket: messages delivered to a component the client may not invoke CVE-2026-82558 (LOW): https://lists.apache.org/thread/o1ojfn53742ztd13m93336t3kdjw2tq9 WebSocketBehavior called onMessage() without the canCallListener() check that Ajax behaviors get, so client messages reached behaviors on components that were hidden, disabled or denied by the authorization strategy. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Native WebSocket: session state survives invalidation CVE-2026-82559 (LOW): https://lists.apache.org/thread/5vkw9wz6gf135ccosj928zjs4hqy7bcv Each connection resolved its Wicket session from a copy of the HTTP session taken at the handshake, so after a container logout, an idle timeout or HttpSession#invalidate() the connection went on acting with the revoked identity. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Authorization bypass through a listener URL without a page id CVE-2026-82704 (MEDIUM): https://lists.apache.org/thread/yrtov7vfmj7c7wl7j1tt0dsv2t0zwy9b A bookmarkable listener URL with an empty page identifier constructed a new page and invoked the listener before Component#configure() had run, so a component denied RENDER by the authorization strategy, or hidden or disabled in onConfigure(), was still invoked. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Authorization strategy not applied to an IResource held by a component CVE-2026-82705 (MEDIUM): https://lists.apache.org/thread/t9y3sho3wkqkr1vsf74xn8tzmgdr1tgo ResourceLink, Image, ImageButton and AjaxDownloadBehavior served an IResource instance from their own listener rather than through ResourceRequestHandler, so isResourceAuthorized() and @AuthorizeResource were skipped; ExportToolbar builds its export links this way. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Auth-Roles: session fixation on re-authentication CVE-2026-82840 (HIGH): https://lists.apache.org/thread/q812kjb74x2pt6956w0pcmkc4wwj95l9 AuthenticatedWebSession#signIn() renewed the session id only on the first transition to signed in, so a session that was already signed in and authenticated again kept the id an attacker may have planted. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.18.0 before 8.20.0, from 9.23.0 before 9.25.0, from 10.9.0 before 10.12.0
Apache Wicket: Resource isolation bypass through the login redirect CVE-2026-82898 (LOW): https://lists.apache.org/thread/bm4mlwsgftxfg345zvdqj0skg1mktpyp ResourceIsolationRequestCycleListener instantiated the target page before consulting its policies, so a RestartResponseAtInterceptPageException from the authorization strategy skipped them, and the cross-origin URL it stored was replayed same-origin once the user signed in. Fixed in: 9.25.0, 10.12.0 Affected: from 9.1.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: AjaxNewWindowNotifyingBehavior: stored cross-site scripting through the window name CVE-2026-82956 (HIGH): https://lists.apache.org/thread/fs3vdddt9bwshdstj952psj49s5w4vqm The window name reported by the browser was kept in the page state and substituted unescaped into a JavaScript string literal on every later render, so a name containing a quote ran as script. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: SmartLinkLabel: cross-site scripting through a script-executing URL scheme CVE-2026-83539 (HIGH): https://lists.apache.org/thread/xqdymd8g178sc112lmqbp53zlss53cwz DefaultLinkParser turned any scheme://... text in the model into a link without a list of permitted schemes, so data naming a scheme that executes script became a link that runs it when clicked; the default CSP of 9.x and 10.x blocks it, 8.x has none. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: JavaScriptUtils: escapeQuotes() does not escape the backslash CVE-2026-83559 (HIGH): https://lists.apache.org/thread/77kc85ztkxdpp7wg7cv61c4539j9s1g3 escapeQuotes() escaped quotes but not the backslash, so a value with a backslash before a quote closed its string literal; this affects application code that calls the method and the error message of AjaxEditableLabel. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: FileUploadToResourceField: client-asserted upload result and unbounded allocation CVE-2026-83594 (HIGH): https://lists.apache.org/thread/h5lxspxg746pzjd437n3n7mq5t3sfbcb The upload callback built its UploadInfo list from client-supplied JSON without binding it to an upload that happened, and UploadInfo#get() allocated a byte array of the claimed size, so one small request could cost close to two gigabytes of heap. Fixed in: 9.25.0, 10.12.0 Affected: from 9.14.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: File upload resource: configured upload limits not enforced CVE-2026-84170 (HIGH): https://lists.apache.org/thread/bw3hn5cch3q7yrsl05m8mvmgyx4m98y7 AbstractFileUploadResource took maxSize, fileMaxSize and fileCountMax from the request parameters, so an unauthenticated client could override the limits configured on FileUploadToResourceField and fill disk or heap. Fixed in: 9.25.0, 10.12.0 Affected: from 9.14.0 before 9.25.0, from 10.0.0 through 10.9.1
Apache Wicket: PackageResourceGuard: markup disclosure with a separate class loader CVE-2026-84172 (MEDIUM): https://lists.apache.org/thread/90mlx42q7nkdccdby1ql1ksl4sxy13x6 The guard looked for the component class beside an HTML file through wicket-core's own class loader, so where wicket-core cannot see the application's classes (a shared library directory, an EAR library, OSGi) component markup templates were served as package resources. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: PackageResource: markup disclosure for class names containing an underscore CVE-2026-84177 (MEDIUM): https://lists.apache.org/thread/hy089v60t5v36skpnbry96vr2427lw0o The guard checked the path before the style, variation and locale from the URL were appended to it, so a shorter name completed by a style resolved to the markup template of a component such as Reportv2, which was then served. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: ExternalLink: cross-site scripting through the model URL CVE-2026-84231 (HIGH): https://lists.apache.org/thread/39kz9838w25797bpkxn1hvfsm8jtc4zv Bound to a tag other than a, link or area, ExternalLink wrote the model URL into a JavaScript string in the onclick handler with only markup escaping, which the browser undoes, so a quote in the URL closed the literal. Fixed in: 8.20.0 Affected: from 8.0.0 before 8.20.0
Apache Wicket: CSP headers omitted behind nested request handler delegates CVE-2026-87718 (LOW): https://lists.apache.org/thread/fjq8v35zpkbtjwpzwkkpzocwtdgokp1m Only one IRequestHandlerDelegate level was unwrapped when deciding whether a request renders a page, so a page behind two or more delegates, such as a custom mapper combined with CryptoMapper, was served without its Content-Security-Policy. Fixed in: 9.25.0, 10.12.0 Affected: 9.24.0, from 10.10.0 before 10.12.0
Apache Wicket: Cross-site scripting through component and markup ids CVE-2026-95863 (HIGH): https://lists.apache.org/thread/5wg754b873tlnsc268myrwcoy9lt046v Markup ids and form input names were written into generated JavaScript string literals without escaping, in wicket-core and several wicket-extensions components, so an application-supplied id containing a quote or backslash ran as script past the default CSP; the fixed versions reject such ids. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Apache Wicket: Cross-site scripting through resource bundle texts CVE-2026-111089 (HIGH): https://lists.apache.org/thread/xyp4sm5mm7s618fktstb22577qxbmqw8 Texts and css classes read from resource bundles were written into JavaScript string literals and attribute values without escaping by MultiFileUploadField, Form, UploadProgressBar, FilterForm and TrapFocusBehavior, so a text containing a quote broke out of its context. Fixed in: 8.20.0, 9.25.0, 10.12.0 Affected: from 8.0.0 before 8.20.0, from 9.0.0 before 9.25.0, from 10.0.0 before 10.12.0
Thanks, Emond Papegaaij on behalf of the Apache Wicket PMC
Missing authorization in Apache Wicket.
org.apache.wicket.protocol.ws.api.WebSocketMessageBroadcastHandler, the request handler Wicket's native WebSocket support uses to deliver an incoming frame, resolves the shared resource named by the client's handshake parameter and calls WebSocketResource#onPayload() on it directly, without consulting IAuthorizationStrategy#isResourceAuthorized(). That method has a single enforcement point in the framework, org.apache.wicket.request.handler.resource.ResourceRequestHandler, which the WebSocket transport does not pass through, and WebSocketResource#respond() is final and empty. No route to a WebSocketResource therefore asks the configured authorization strategy whether the caller may use it, and an @AuthorizeResource annotation on such a class has no effect.
A caller needs a bound Wicket session and the name of the resource. The name is not a secret: Wicket writes it into the page that opens the connection. No page of the application is otherwise involved, because a request naming a resource is served with a throwaway page. All of the resource's callbacks are reached this way, including onConnect() and both onMessage() overloads, and what a callback pushes back through WebSocketRequestHandler goes to the caller's own connection.
An application is affected where it registers a WebSocketResource as a shared resource and relies on the authorization strategy to restrict it. What the caller gains is whatever that resource's callbacks do with a text or binary message of the caller's choosing. The connection is registered under the caller's own session, so it gives no access to another user's connection.
As a workaround, reject unauthorized connections with an IWebSocketConnectionFilter registered through WebSocketSettings#setConnectionFilter(), or repeat the authorization check at the start of each callback.
This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Older, unsupported releases from 7.0.0 onwards are also affected. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.html.form.AbstractSingleSelectChoice, the base class of DropDownChoice, writes the body of the default option — the entry shown when no choice is selected — into the markup as it is, while every other option body in the same select is escaped according to the escape-model-strings setting. The body comes from getNullValidDisplayValue() or getNullKeyDisplayValue(), both of which are protected, so what they return is not necessarily the plain text the default implementation reads from a resource bundle.
An application is affected where it overrides one of those methods and returns a value holding data an attacker can influence, or where its own nullValid or null bundle entry holds such a value. The bundles shipped with Wicket contain plain text. RadioChoice overrides getDefaultChoice to emit no default option and is not affected.
As a workaround, escape the value in the override.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.5.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.extensions.markup.html.form.palette.component.AbstractOptions, which renders the two option lists of a Palette, escapes the id and the display value of each option according to the escape-model-strings setting, and wrote the attribute names and values returned by getAdditionalAttributes into the <option> tag as they came.
An application is affected where it overrides Palette.getAdditionalAttributesForChoices, Palette.getAdditionalAttributesForSelection or AbstractOptions.getAdditionalAttributes and returns a value holding data an attacker can influence. These methods return null by default, so an application that does not override them is not affected.
As a workaround, escape the values in the override.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.4.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.head.MetaDataHeaderItem generates <meta> and <link> header tags. It escaped the attribute names it wrote, but ran the attribute values through a replacement of " with \". A backslash before a double quote means nothing in HTML, so a value containing a double quote ends its own attribute and what follows is parsed as further attributes of the generated tag.
An application is affected where it supplies an attribute value holding data an attacker can influence, through addTagAttribute or the forMetaTag and forLinkTag factory methods. A value may be given as an IModel, so it is not necessarily a literal.
There is no setting to change; an application can only avoid supplying a value that contains a double quote. Note that these values have never been escaped effectively: before the change released in 6.24.0, 7.4.0 and 8.0.0 they were written with no escaping at all.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 6.17.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
The <wicket:label> tag is provided by org.apache.wicket.markup.html.form.AutoLabelTextResolver, which is registered by default in every WebApplication. The resolver writes the label it finds into the markup as it is, and reads no escaping setting at all, so markup in a label is rendered as markup.
When the label comes from the labelled component's label model, set through FormComponent#setLabel(IModel), it is written to the markup unescaped. An application is affected where the label of a form component holds data an attacker can influence. Wicket cannot determine where a model value comes from, so whether it reaches the page from a request or from storage is a property of the application.
There is no workaround. Unlike every other rendering path in Wicket, the resolver never consulted the escape-model-strings setting, so an application had no way to ask for the label to be escaped.
The body of a <wicket:label> tag is markup by design and is not affected; it remains the supported way to place markup in a label.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.5.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.html.form.Button clears the escape-model-strings flag in its constructor, so that the value attribute it writes is not encoded twice — ComponentTag already encodes attribute values when it writes the tag. That reasoning holds only for the attribute. When the component is attached to a <button> element rather than an <input>, it writes its model object into the element body instead, and nothing encodes an element body, so markup in the model is rendered as markup.
An application is affected where it renders a Button on a <button> element and that button's model holds data an attacker can influence. Wicket cannot determine where a model value comes from, so whether it reaches the page from a request or from storage is a property of the application. The subclasses that inherit this constructor — AjaxButton, AjaxFallbackButton and WizardButton — are affected on the same terms.
As a workaround, calling setEscapeModelStrings(true) on a button that renders as a <button> element escapes the body correctly, and does not cause double encoding, because the value attribute is written only for <input> elements.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 6.25.0 and 7.5.0 onwards are also affected.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
AjaxEditableChoiceLabel in wicket-extensions, when constructed with a non-null IChoiceRenderer, writes the display value obtained from that renderer into the label's markup without applying the HTML escaping Wicket performs by default for component model values. An attacker who can influence the choice or model data rendered by such a label can inject HTML or script that executes in the browser of any user who views the page. The same value is correctly escaped when the component's dropdown editor renders it as an option, so only the label rendering is affected.
AjaxEditableLabel, AjaxEditableChoiceLabel and AjaxEditableMultiLineLabel write the value returned by the protected defaultNullLabel() method into the label's markup the same way when the component's model is empty, while the model value they show otherwise is escaped. The default implementation returns a constant, so an application is affected where it overrides that method and returns a value an attacker can influence.
Neither value could be escaped by configuration, because escapeModelStrings had no effect on any of the three components: it is read by the label they render with rather than by the component itself, and nothing carried the setting across.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases are also affected; the display value from the renderer since 6.22.0 and the null label since 1.4.0. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Severity: moderate
Affected versions:
- Apache Wicket (org.apache.wicket:wicket-core) 8.0.0 through 8.18.0 - Apache Wicket (org.apache.wicket:wicket-core) 9.0.0 through 9.23.0 - Apache Wicket (org.apache.wicket:wicket-core) 10.0.0 through 10.10.0
Description:
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.html.form.Button clears the escape-model-strings flag in its constructor, so that the value attribute it writes is not encoded twice — ComponentTag already encodes attribute values when it writes the tag. That reasoning holds only for the attribute. When the component is attached to a <button> element rather than an <input>, it writes its model object into the element body instead, and nothing encodes an element body, so markup in the model is rendered as markup.
An application is affected where it renders a Button on a <button> element and that button's model holds data an attacker can influence. Wicket cannot determine where a model value comes from, so whether it reaches the page from a request or from storage is a property of the application. The subclasses that inherit this constructor — AjaxButton, AjaxFallbackButton and WizardButton — are affected on the same terms.
As a workaround, calling setEscapeModelStrings(true) on a button that renders as a <button> element escapes the body correctly, and does not cause double encoding, because the value attribute is written only for <input> elements.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 6.25.0 and 7.5.0 onwards are also affected.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Credit:
Emond Papegaaij (finder)
References:
https://wicket.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-76982
Severity: moderate
Affected versions:
- Apache Wicket (org.apache.wicket:wicket-core) 8.0.0 through 8.18.0 - Apache Wicket (org.apache.wicket:wicket-core) 9.0.0 through 9.23.0 - Apache Wicket (org.apache.wicket:wicket-core) 10.0.0 through 10.10.0
Description:
Improper neutralization of input during web page generation in Apache Wicket.
The <wicket:label> tag is provided by org.apache.wicket.markup.html.form.AutoLabelTextResolver, which is registered by default in every WebApplication. The resolver writes the label it finds into the markup as it is, and reads no escaping setting at all, so markup in a label is rendered as markup.
When the label comes from the labelled component's label model, set through FormComponent#setLabel(IModel), it is written to the markup unescaped. An application is affected where the label of a form component holds data an attacker can influence. Wicket cannot determine where a model value comes from, so whether it reaches the page from a request or from storage is a property of the application.
There is no workaround. Unlike every other rendering path in Wicket, the resolver never consulted the escape-model-strings setting, so an application had no way to ask for the label to be escaped.
The body of a <wicket:label> tag is markup by design and is not affected; it remains the supported way to place markup in a label.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.5.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Credit:
Ho1aAs (finder)
References:
https://wicket.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-76983
Severity: moderate
Affected versions:
- Apache Wicket (org.apache.wicket:wicket-core) 8.0.0 through 8.18.0 - Apache Wicket (org.apache.wicket:wicket-core) 9.0.0 through 9.23.0 - Apache Wicket (org.apache.wicket:wicket-core) 10.0.0 through 10.10.0
Description:
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.head.MetaDataHeaderItem generates <meta> and <link> header tags. It escaped the attribute names it wrote, but ran the attribute values through a replacement of " with \". A backslash before a double quote means nothing in HTML, so a value containing a double quote ends its own attribute and what follows is parsed as further attributes of the generated tag.
An application is affected where it supplies an attribute value holding data an attacker can influence, through addTagAttribute or the forMetaTag and forLinkTag factory methods. A value may be given as an IModel, so it is not necessarily a literal.
There is no setting to change; an application can only avoid supplying a value that contains a double quote. Note that these values have never been escaped effectively: before the change released in 6.24.0, 7.4.0 and 8.0.0 they were written with no escaping at all.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 6.17.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Credit:
Emond Papegaaij (finder)
References:
https://wicket.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-76984
Severity: moderate
Affected versions:
- Apache Wicket (org.apache.wicket:wicket-core) 8.0.0 through 8.18.0 - Apache Wicket (org.apache.wicket:wicket-core) 9.0.0 through 9.23.0 - Apache Wicket (org.apache.wicket:wicket-core) 10.0.0 through 10.10.0
Description:
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.html.form.AbstractSingleSelectChoice, the base class of DropDownChoice, writes the body of the default option — the entry shown when no choice is selected — into the markup as it is, while every other option body in the same select is escaped according to the escape-model-strings setting. The body comes from getNullValidDisplayValue() or getNullKeyDisplayValue(), both of which are protected, so what they return is not necessarily the plain text the default implementation reads from a resource bundle.
An application is affected where it overrides one of those methods and returns a value holding data an attacker can influence, or where its own nullValid or null bundle entry holds such a value. The bundles shipped with Wicket contain plain text. RadioChoice overrides getDefaultChoice to emit no default option and is not affected.
As a workaround, escape the value in the override.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.5.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
Credit:
Emond Papegaaij (finder)
References:
https://wicket.apache.org/ https://www.cve.org/CVERecord?id=CVE-2026-76986
ResourceIsolationRequestCycleListener protects a Wicket application against cross-site request forgery by rejecting requests that a resource isolation policy judges to come from another origin. Its default policy, FetchMetadataResourceIsolationPolicy, was derived from a reference implementation written to guard static resources, and it inherited two allowances that are unsafe when the thing being guarded is an action on a page: Every "simple top-level navigation" was allowed. Any GET request carrying Sec-Fetch-Mode: navigate whose Sec-Fetch-Dest was neither object nor embed was allowed, whatever Sec-Fetch-Site said — including cross-site. Wicket invokes component listeners (Link.onClick(), form submits, behaviour callbacks) through ordinary GET navigations, so a page under an attacker's control could navigate the victim's browser to a listener URL and have that listener run inside the victim's authenticated session. Browsers send SameSite=Lax cookies — the effective default when no SameSite attribute is set — on cross-site top-level GET navigations, so the victim's session cookie accompanied the request. Sec-Fetch-Site: same-site was allowed unconditionally. That value means the same registrable domain and scheme but a different origin — another subdomain or another port. Any sibling origin could therefore invoke any listener by any method, POST form submits included, and cookies are always sent on same-site requests regardless of SameSite. A hostile sibling origin obtained through a subdomain takeover, through delegated user content, or through an XSS elsewhere on the site could act as the authenticated user. Users are recommended to upgrade to version 9.24.0 or 10.11.0, which fix the issue. Affected versions
Apache Wicket 9.1.0 through 9.23.0 Apache Wicket 10.0.0 through 10.10.0
Not affected
Any release older than 9.1.0: Apache Wicket 8.x (8.0.0 through 8.17.0). The resource isolation classes do not exist in the 8.x line, which offers only the Origin/Referer-based CsrfPreventionRequestCycleListener. No 8.x release requires a fix. Apache Wicket 9.0.0. ResourceIsolationRequestCycleListener and FetchMetadataResourceIsolationPolicy were introduced by WICKET-6786 and first shipped in 9.1.0 (released 2020-10-07).
Apache Wicket enforces the upload limits configured on a form or upload field while parsing a multipart request with Apache Commons FileUpload. If the request body has already been consumed by another component, Commons FileUpload returns no items and Wicket falls back to reading the upload through HttpServletRequest#getParts(). The per-file size limit (for example Form#setFileMaxSize) and the file count limit (Form#setFileCountMax) are not applied to the parts obtained that way, and no exception is raised, so the upload is processed as though those limits had been satisfied. A remote uploader can therefore submit files that are larger, or more numerous, than the application permits, up to whatever the component that parsed the request allows. A part carrying no Content-Type header is additionally read into memory in full during parsing, so the size of that allocation is determined by the request and bounded only by those same external limits.
The total upload size limit (Form#setMaxSize) is not affected. Commons FileUpload compares the declared Content-Length against it before reading the body, so a request declaring an oversized length is rejected before the fallback is reached.
The fallback is reached in deployments where a servlet or filter has already parsed the request body — for example a servlet annotated with @MultipartConfig, Spring Boot's multipart resolver, or any filter that calls HttpServletRequest#getParameter() on a multipart request. It applies to the Wicket components that accept uploads on that path, including Form with FileUploadField, FileUploadToResourceField and AjaxFileDropBehavior. Applications that configure neither a per-file nor a file-count limit are not affected, as Wicket applies neither by default.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. As a workaround, configure equivalent limits in the component that parses the request — for example spring.servlet.multipart.max-file-size and max-request-size, or maxFileSize and maxRequestSize in @MultipartConfig or in the web.xml <multipart-config> element.
Improper validation of resource URL attributes in Apache Wicket allows an unauthenticated remote attacker to read files from the web application, including files under WEB-INF that the servlet container would not otherwise serve.
The locale, style and variation attributes decoded from a package resource URL are spliced into the resource lookup path without being checked for path separators. The IPackageResourceGuard — whose rejection of .. is one of the two intended controls — is applied to the resource name before those attributes are appended, and WebApplicationPath rejects only paths literally beginning with WEB-INF/. Neither control ever inspects the attacker-controlled portion of the path. On servlet containers that normalize .. in ServletContext.getResource(), a crafted request therefore escapes the intended package directory.
The set of readable files is limited to the file extensions permitted by the configured IPackageResourceGuard. The default SecurePackageResourceGuard permits only js, css, png, jpg, jpeg, gif, ico, cur, map, html, txt, swf, bmp, svg, avif, eot, ttf, woff and woff2, which excludes configuration formats. Applications that have added patterns to the guard, or replaced it with the blocklist-based PackageResourceGuard, can additionally disclose configuration files such as web.xml. Independently of the extension, the lookup performed before the guard runs acts as an existence oracle for arbitrary paths.
This issue affects Apache Wicket 8.18.0 and before, 9.23.0 and before and 10.10.0 and before.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version.