GHSA-63v5-26vq-m4vm

Keycloak's missing timestamp validation allows attackers to extend SAML response validity periods

At a glance

Published: 2026-01-26 21:30 UTC
Updated: 2026-09-10 03:49 UTC
CVE: CVE-2026-1190
CVSS_V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N

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.

Affected packages

Package	Versions
Maven · org.keycloak:keycloak-services	introduced 0, last affected 26.5.2

References

https://nvd.nist.gov/vuln/detail/CVE-2026-1190 ADVISORY
https://github.com/keycloak/keycloak/issues/45646 WEB
https://access.redhat.com/errata/RHSA-2026:3947 WEB
https://access.redhat.com/errata/RHSA-2026:3948 WEB
https://access.redhat.com/security/cve/CVE-2026-1190 WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2430835 WEB
https://github.com/keycloak/keycloak WEB

Sources

Source	Licence
OSV.dev	CC-BY 4.0 — GitHub Advisory Database