A flaw was found in the Undertow DEBUG log for io.undertow.request.security. If enabled, an attacker could abuse this flaw to obtain the user’s credentials from the log files.

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests. As a result, requests containing malformed or malicious Host headers are processed without rejection, enabling attackers to poison caches, perform internal network scans, or hijack user sessions.

A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure.

A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request smuggling attacks, potentially bypassing security controls and accessing unauthorized resources.

A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending \r\r\r as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.

A flaw was found when an OpenSSL security provider is used with Wildfly, the 'enabled-protocols' value in the Wildfly configuration isn't honored. An attacker could target the traffic sent from Wildfly and downgrade the connection to a weaker version of TLS, potentially breaking the encryption. This could lead to a leak of the data being passed over the network.

A security flaw in the IdentityBrokerService.performLogin endpoint of Keycloak allows authentication to proceed using an Identity Provider (IdP) even after it has been disabled by an administrator. An attacker who knows the IdP alias can reuse a previously generated login request to bypass the administrative restriction. This undermines access control enforcement and may allow unauthorized authentication through a disabled external provider.

A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing slash or matrix parameters to a URL, an attacker can trick the system into applying a less restrictive security policy than intended. This allows an authenticated user to access administrative or restricted areas they should not have permission to see.

A flaw was found in Keycloak where the default Dynamic Client Registration (DCR) policy permits the use of User Property mappers without validating the target claim path. While the policy checks the mapper provider type, it does not restrict where the mapper can write data within the resulting token. An attacker with a standard user account and a limited Initial Access Token (IAT) can register a new client and configure User Property mappers (such as firstName or lastName) to target the resourceaccess.realm-management.roles claim path. By setting their user profile properties to administrative role names (e.g., manage-clients, realm-admin), the attacker can produce a forged access token containing these roles. Although recent mitigations (CVE-2026-4629) protect the Admin REST API from such forged tokens, the Client Registration API remains vulnerable because it reads the resourceaccess claim directly during authorization. An attacker can use this bypass to perform unauthorized DCR operations, including reading confidential client secrets, modifying redirect URIs, and impersonating service accounts to achieve full realm compromise.

A flaw was found in all undertow-2.x.x SP1 versions prior to undertow-2.0.30.SP1, all undertow-1.x.x and undertow-2.x.x versions prior to undertow-2.1.0.Final, where the Servlet container causes servletPath to normalize incorrectly by truncating the path after semicolon which may lead to an application mapping resulting in the security bypass.

A vulnerability was found in Undertow where the ProxyProtocolReadListener reuses the same StringBuilder instance across multiple requests. This issue occurs when the parseProxyProtocolV1 method processes multiple requests on the same HTTP connection. As a result, different requests may share the same StringBuilder instance, potentially leading to information leakage between requests or responses. In some cases, a value from a previous request or response may be erroneously reused, which could lead to unintended data exposure. This issue primarily results in errors and connection termination but creates a risk of data leakage in multi-request environments.

A denial of service vulnerability was found in keycloak where the amount of attributes per object is not limited, an attacker by sending repeated HTTP requests could cause a resource exhaustion when the application send back rows with long attribute values. The issue is fixed in Keycloak 24 with the introduction of the User Profile feature.

A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters. This issue, referred to as the "MadeYouReset" attack, allows malicious clients to induce excessive server workload by repeatedly causing server-side stream aborts. While not a protocol bug, this highlights a common implementation weakness that can be exploited to cause a denial of service (DoS).

A flaw was found in JBoss-client. The vulnerability occurs due to a memory leak on the JBoss client-side, when using UserTransaction repeatedly and leads to information leakage vulnerability.

A flaw was found in Keycloak. This flaw allows an attacker to perform a denial of service attack by sending multiple simultaneous requests with a Content-Length header value greater than the actual byte count of the request body. The highest threat from this vulnerability is to system availability.

A flaw was found in XNIO, specifically in the notifyReadClosed method. The issue revealed this method was logging a message to another expected end. This flaw allows an attacker to send flawed requests to a server, possibly causing log contention-related performance concerns or an unwanted disk fill-up.

A vulnerability was found in the Undertow HTTP server in versions before 2.0.28.SP1 when listening on HTTPS. An attacker can target the HTTPS port to carry out a Denial Of Service (DOS) to make the service unavailable on SSL.

HTTP/2 Rapid reset attack The HTTP/2 protocol allows clients to indicate to the server that a previous stream should be canceled by sending a RSTSTREAM frame. The protocol does not require the client and server to coordinate the cancellation in any way, the client may do it unilaterally. The client may also assume that the cancellation will take effect immediately when the server receives the RSTSTREAM frame, before any other data from that TCP connection is processed.

Abuse of this feature is called a Rapid Reset attack because it relies on the ability for an endpoint to send a RSTSTREAM frame immediately after sending a request frame, which makes the other endpoint start working and then rapidly resets the request. The request is canceled, but leaves the HTTP/2 connection open.

The HTTP/2 Rapid Reset attack built on this capability is simple: The client opens a large number of streams at once as in the standard HTTP/2 attack, but rather than waiting for a response to each request stream from the server or proxy, the client cancels each request immediately.

The ability to reset streams immediately allows each connection to have an indefinite number of requests in flight. By explicitly canceling the requests, the attacker never exceeds the limit on the number of concurrent open streams. The number of in-flight requests is no longer dependent on the round-trip time (RTT), but only on the available network bandwidth.

In a typical HTTP/2 server implementation, the server will still have to do significant amounts of work for canceled requests, such as allocating new stream data structures, parsing the query and doing header decompression, and mapping the URL to a resource. For reverse proxy implementations, the request may be proxied to the backend server before the RSTSTREAM frame is processed. The client on the other hand paid almost no costs for sending the requests. This creates an exploitable cost asymmetry between the server and the client.

Multiple software artifacts implementing HTTP/2 are affected. This advisory was originally ingested from the swift-nio-http2 repo advisory and their original conent follows.

swift-nio-http2 specific advisory swift-nio-http2 is vulnerable to a denial-of-service vulnerability in which a malicious client can create and then reset a large number of HTTP/2 streams in a short period of time. This causes swift-nio-http2 to commit to a large amount of expensive work which it then throws away, including creating entirely new Channels to serve the traffic. This can easily overwhelm an EventLoop and prevent it from making forward progress.

swift-nio-http2 1.28 contains a remediation for this issue that applies reset counter using a sliding window. This constrains the number of stream resets that may occur in a given window of time. Clients violating this limit will have their connections torn down. This allows clients to continue to cancel streams for legitimate reasons, while constraining malicious actors.

A flaw was found in the Java logging library Apache Log4j in version 1.x . This allows a remote attacker to execute code on the server if the deployed application is configured to use JMSAppender.

In 1.x you will find that there are two places where lookups are done - that is JMSAppender.java:207 and JMSAppender.java:222 - if you set TopicBindingName or TopicConnectionFactoryBindingName to something that JNDI can handle - for example "ldap://host:port/a" JNDI will do exactly the same thing it does for 2.x - so 1.x is vulnerable, just attack vector is "safer" as it depends on configuration rather than user input

This flaw in Log4j 2.x is tracked via CVE-2021-44228

A flaw was found in keycloak-model-infinispan in keycloak versions before 14.0.0 where authenticationSessions map in RootAuthenticationSessionEntity grows boundlessly which could lead to a DoS attack.

An information leak issue was found in undertow where web apps may have their directory structures predicted through requests without trailing slashes via the api.

A flaw was found in Undertow. When an AJP request is sent that exceeds the max-header-size attribute in ajp-listener, JBoss EAP is marked in an error state by modcluster in httpd, causing JBoss EAP to close the TCP connection without returning an AJP response. This happens because modproxycluster marks the JBoss EAP instance as an error worker when the TCP connection is closed from the backend after sending the AJP request without receiving an AJP response, and stops forwarding. This issue could allow a malicious user could to repeatedly send requests that exceed the max-header-size, causing a Denial of Service (DoS).

A flaw was found in Keycloak. An administrator with manage-clients permission can exploit a misconfiguration where this permission is equivalent to manage-permissions. This allows the administrator to escalate privileges and gain control over roles, users, or other administrative functions within the realm. This privilege escalation can occur when admin permissions are enabled at the realm level.

A flaw was found in keycloak. The vulnerability allows arbitrary Javascript to be uploaded for the SAML protocol mapper even if the UPLOADSCRIPTS feature is disabled.

A flaw was found in Keycloak 12.0.0 where re-authentication does not occur while updating the password. This flaw allows an attacker to take over an account if they can obtain temporary, physical access to a user’s browser. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

A flaw was found in keycloak, where the default ECP binding flow allows other authentication flows to be bypassed. By exploiting this behavior, an attacker can bypass the MFA authentication by sending a SOAP request with an AuthnRequest and Authorization header with the user's credentials. The highest threat from this vulnerability is to confidentiality and integrity.

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-5cc8-pgp5-7mpm. This link is maintained to preserve external references.

Original Advisory A flaw was found in Keycloak. This flaw depends on a non-default configuration "Revalidate Client Certificate" to be enabled and the reverse proxy is not validating the certificate before Keycloak. Using this method an attacker may choose the certificate which will be validated by the server. If this happens and the KCSPITRUSTSTOREFILEFILE variable is missing/misconfigured, any trustfile may be accepted with the logging information of "Cannot validate client certificate trust: Truststore not available". This may not impact availability as the attacker would have no access to the server, but consumer applications Integrity or Confidentiality may be impacted considering a possible access to them. Considering the environment is correctly set to use "Revalidate Client Certificate" this flaw is avoidable.

A vulnerability was found in Wildfly's EJB where SessionOpenInvocations may not be removed properly after a response is received after a response is received causing Denial of Service.

A flaw was discovered in Wildfly's EJB Client as shipped with Red Hat JBoss EAP 7, where some specific EJB transaction objects may get accumulated over the time and can cause services to slow down and eventaully unavailable. An attacker can take advantage and cause denial of service attack and make services unavailable.

A flaw was found in JBoss EAP, where the authentication configuration is set-up using a legacy SecurityRealm, to delegate to a legacy PicketBox SecurityDomain, and then reloaded to admin-only mode. This flaw allows an attacker to perform a complete authentication bypass by using an arbitrary user and password. The highest threat to vulnerability is to system availability.