Authentication Bypass Affecting rh-sso7-keycloak-server package, versions <0:18.0.20-1.redhat_00001.1.el7sso


Severity

Recommended
0.0
high
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
1.1% (65th percentile)

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  • Snyk IDSNYK-RHEL7-RHSSO7KEYCLOAKSERVER-21089171
  • published16 Oct 2026
  • disclosed19 May 2026

Introduced: 19 May 2026

CVE-2026-7507  (opens in a new tab)
CWE-290  (opens in a new tab)

How to fix?

Upgrade RHEL:7 rh-sso7-keycloak-server to version 0:18.0.20-1.redhat_00001.1.el7sso or higher.
This issue was patched in RHSA-2026:76128.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rh-sso7-keycloak-server package and not the rh-sso7-keycloak-server package as distributed by RHEL. See How to fix? for RHEL:7 relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1