Description
A flaw was found in Keycloak's SAML brokering functionality. When Keycloak is configured as a client in a Security Assertion Markup Language (SAML) setup, it fails to validate the `NotOnOrAfter` timestamp within the `SubjectConfirmationData`. This allows an attacker to delay the expiration of SAML responses, potentially extending the time a response is considered valid and leading to unexpected session durations or resource consumption.
Problem types
Product status
Timeline
| 2026-01-19: | Reported to Red Hat. |
| 2026-01-19: | Made public. |
Credits
Red Hat would like to thank Franz Bettag (Bettag Systems) for reporting this issue.
References
access.redhat.com/security/cve/CVE-2026-1190
bugzilla.redhat.com/show_bug.cgi?id=2430835 (RHBZ#2430835)