Description
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.
Problem types
Authentication Bypass by Spoofing
Product status
26.2.16-1 (rpm) before *
26.2-21 (rpm) before *
26.2-21 (rpm) before *
26.4.12-1 (rpm) before *
26.4-17 (rpm) before *
26.4-17 (rpm) before *
Timeline
| 2026-04-30: | Reported to Red Hat. |
| 2026-05-19: | Made public. |
Credits
Red Hat would like to thank Hacking Team (Calif.io) for reporting this issue.
References
access.redhat.com/errata/RHSA-2026:19594 (RHSA-2026:19594)
access.redhat.com/errata/RHSA-2026:19595 (RHSA-2026:19595)
access.redhat.com/errata/RHSA-2026:19596 (RHSA-2026:19596)
access.redhat.com/errata/RHSA-2026:19597 (RHSA-2026:19597)
access.redhat.com/security/cve/CVE-2026-7507
bugzilla.redhat.com/show_bug.cgi?id=2464145 (RHBZ#2464145)