A session fixation vulnerability was found in Keycloak's login-actions endpoints. An unauthenticated attacker could exploit this flaw by pre-creating an authentication session and tricking a victim into visiting a maliciously crafted link. By leveraging the /login-actions/restart endpoint—which processes session handles without adequate CSRF protection or cookie ownership validation—an attacker can reset the authentication flow state. This causes Single Sign-On (SSO) to authenticate the victim transparently upon clicking the link, allowing the attacker to hijack the required-action form without needing the victim's credentials. A successful exploit could lead to complete account takeover, including highly privileged administrative accounts.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - A session fixation vulnerability was found in Keycloak's login-actions endpoints. An unauthenticated
    attacker could exploit this flaw by pre-creating an authentication session and tricking a victim into
    visiting a maliciously crafted link. By leveraging the /login-actions/restart endpoint—which processes
    session handles without adequate CSRF protection or cookie ownership validation—an attacker can reset the
    authentication flow state. This causes Single Sign-On (SSO) to authenticate the victim transparently upon
    clicking the link, allowing the attacker to hijack the required-action form without needing the victim's
    credentials. A successful exploit could lead to complete account takeover, including highly privileged
    administrative accounts. (CVE-2026-7507)

Keycloak versions installed prior to 26.6.2 are affected by multiple vulnerabilities, including:

  - A flaw was found in Keycloak's redirect URI validation logic. An attacker can bypass     validation to redirect users to malicious sites, potentially leading to phishing attacks and     credential theft. (CVE-2026-7504)

  - A session fixation vulnerability exists in the OIDC login flow. An unauthenticated attacker     can pre-create sessions leading to account takeover if a user logs in using the attacker's     session. (CVE-2026-7507)

  - A flaw was found in Keycloak's SAML endpoint processing. A crafted XML request to the SAML     endpoint can cause a denial of service by consuming excessive server resources. (CVE-2026-7307)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
442651	SCA: security update for org.keycloak:keycloak-services (GHSA-hf67-5vvq-fm3r)	Tenable Cloud Security	SCA Checks	high
442651	SCA: security update for org.keycloak:keycloak-services (GHSA-hf67-5vvq-fm3r)	Tenable Self-Hosted Container Security	SCA Checks	high
316461	Keycloak < 26.6.2 Multiple Vulnerabilities	Nessus	Misc.	medium

Detections

Analytics

CVE-2026-7507

high

Tenable Plugins

high

high

medium