CVE-2026-7507
Keycloak: Session fixation in OIDC login flow that can lead to account takeover
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.
How to fix CVE-2026-7507
To remediate CVE-2026-7507, upgrade the affected package to a fixed version below.
- —upgrade to 26.6.2 or later
Is CVE-2026-7507 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-7507.
Affected packages (1)
- from 0, < 26.6.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |