A cross-site request forgery (CSRF) vulnerability exists in MISP due to form-security and CSRF protections being disabled based on whether an incoming request was identified as a REST request.

MISP's REST detection can be influenced by request properties such as the URL suffix or the HTTP Accept header. Because Accept: application/json can be supplied by a cross-origin page without requiring a CORS preflight, an attacker could cause a request originating from another website to be treated as REST traffic. MISP would consequently disable its normal form-security and CSRF validation even though the request was authenticated using the victim's existing browser session.

An unauthenticated remote attacker could exploit this behavior by convincing an authenticated MISP user to visit or interact with a malicious web page. The attacker's page could then issue crafted requests to susceptible state-changing MISP endpoints using the victim's privileges. Depending on the permissions of the victim and the targeted endpoint, this could allow unauthorized modification, creation, publication, or removal of data and other state changes.

The vulnerability originates from granting the form-security exemption based on isRest() rather than on the authentication mechanism used by the request. The patch changes this behavior so that CSRF and form-security exemptions are granted only when the request actually carries a MISP API key. Session-authenticated REST-style requests remain subject to CSRF protection. The fix also introduces support for transmitting CSRF tokens through the X-CSRF-Token header for legitimate same-origin AJAX requests. Such a header cannot normally be attached by a cross-origin page without triggering a CORS preflight, preventing it from being used to reproduce the original attack.

MISP contains a cross-site request forgery (CSRF) vulnerability in the sharing group quick-edit functionality. The addOrg, removeOrg, addServer, and removeServer actions share the initialiseSGQuickEdit() helper, where the HTTP method validation intended to restrict these operations to POST requests was commented out.

As a result, these state-changing actions could be invoked using GET requests. An attacker could craft a URL targeting one of the affected actions and cause an authenticated MISP user with sufficient privileges to request it, for example through a malicious link or embedded web resource.

Successful exploitation could modify the membership of a MISP sharing group without the victim intentionally performing the operation. Depending on the action performed, an attacker could add or remove organisations or servers from a sharing group, potentially granting unintended access to information distributed through that sharing group or disrupting legitimate information sharing.

The patch restores HTTP method enforcement centrally in initialiseSGQuickEdit() by calling allowMethod(['post']), ensuring that all four affected quick-edit operations require POST requests and are therefore subject to the application's normal protections for state-changing requests.

MISP contains a session fixation vulnerability in the CustomAuth authentication (a custom configuration) flow. When a user was successfully authenticated through CustomAuth, MISP stored the authenticated user identity in the existing session without first rotating the session identifier.

As a result, if an attacker can cause a victim to use a session identifier known to the attacker before authentication, that same session identifier remains valid after the victim successfully authenticates. The attacker could subsequently reuse the fixed session identifier to access the victim's authenticated MISP session, potentially gaining the privileges associated with the victim's account.

The issue occurs because customAuthentication() wrote the authenticated user into the existing CakePHP session while the call to Session->renew() had previously been disabled. The patch restores session identifier rotation when a new authentication occurs or when the authenticated user changes, while avoiding unnecessary session renewal on every request.

A vulnerability in MISP's email-based one-time password (OTP) authentication flow allowed an attacker to perform an unrestricted number of OTP verification attempts.

The emailotp() endpoint did not apply brute-force protection when validating submitted OTP values. An attacker who had reached the OTP verification stage, for example after successfully providing a user's primary authentication credentials, could repeatedly submit candidate OTP values while the same OTP remained valid. This significantly increased the feasibility of guessing the OTP and bypassing the additional authentication factor, potentially resulting in unauthorized access to the affected user's account.

The issue was exacerbated by the fact that the OTP is associated with the user rather than with an individual pending login session, allowing multiple concurrent sessions to attempt guesses against the same valid OTP.

The patch integrates the existing MISP brute-force protection mechanism into the email OTP flow. Failed OTP attempts are now counted against the user, further attempts are rejected once the configured threshold is reached, and the active OTP is invalidated when the attempt budget is exhausted. Blocklisted users are also prevented from requesting the generation of a fresh OTP. In addition, OTP comparison now uses hashequals() and validates that the submitted value is a string.

MISP installation scripts generated an Apache HTTP virtual-host configuration containing an incorrectly formatted HTTP-to-HTTPS redirect:

Redirect permanent / https://misp.example

Apache’s Redirect directive appends any portion of the requested path that follows the matched prefix to the configured destination URL. Because the destination did not end with /, attacker-controlled path content was appended directly to the hostname rather than to its URL path.

For example, a request resembling:

http://misp.example/@attacker.example/

could result in a redirect resembling:

https://misp.example@attacker.example/

Under standard URL parsing, misp.example is interpreted as user information and attacker.example as the destination host. An unauthenticated remote attacker could therefore construct a URL hosted under the legitimate MISP domain that redirects users to an attacker-controlled website.

The vulnerability could be used for phishing, credential collection, or potentially disclosing sensitive query-string information preserved during the redirect. Exploitation requires a user to follow the crafted HTTP URL.

The fix adds the missing trailing slash to the redirect destination, ensuring that appended request data remains part of the path on the configured MISP host.

Existing installationsExisting MISP installations should review their Apache HTTP virtual-host configuration and ensure that the HTTPS redirect destination ends with a trailing slash:

Redirect permanent / https://misp.example/

After updating the configuration, validate it with apachectl configtest and reload or restart Apache for the change to take effect

MISP’s importModule() path used getEnabledModule() to resolve a single import module by name, but this lookup did not enforce the per-organisation module restriction checked by getEnabledModules(). As a result, an authenticated user from an organisation that was not allowed to use a module restricted via Plugin.Import<module>restrict could still invoke that import module directly if they knew its name.

This could allow unauthorised access to restricted import-module functionality and, depending on the module and the user’s event permissions, may allow unauthorised import or modification of event data through a module that should have been unavailable to the user’s organisation.

An authorization bypass in MISP’s EventsController::importModule() allowed authenticated users or read-only API keys with event view access to persist data to events they were not allowed to modify. When an import module returned results in the mispstandard format, the write path did not verify event modification rights before saving the module output. This could allow a view-only user to inject or alter event data, impacting the integrity of MISP event content. The issue was fixed by enforcing the same modification-rights check used by related module result handling paths before processing mispstandard imports.

app/webroot/js/workflows-editor/workflows-editor.js in MISP through 2.5.2 has stored XSS in the editor interface for an ad-hoc workflow.

app/View/GalaxyClusters/clusterexportmispgalaxy.ctp in MISP through 2.5.2 has stored XSS when exporting custom clusters into the misp-galaxy format.

In MISP 2.4.167, app/Controller/Component/ACLComponent.php has incorrect access control for the decaying import function.

In MISP 2.4.167, app/webroot/js/event-graph.js has an XSS vulnerability via an event-graph preview payload.

app/webroot/js/misp.js in MISP 2.4.91 has a DOM based XSS with cortex type attributes.

MISP before 2.4.81 has a potential reflected XSS in a quickDelete action that is used to delete a sighting, related to app/View/Sightings/ajax/quickDeleteConfirmationForm.ctp and app/webroot/js/misp.js.

When MISP before 2.4.80 is configured with X.509 certificate authentication (CertAuth) in conjunction with a non-MISP external user management ReST API, if an external user provides X.509 certificate authentication and this API returns an empty value, the unauthenticated user can be granted access as an arbitrary user.