CVE-2026-1190: Org.keycloak/keycloak-services: keycloak saml brokering: response delay due to unchecked notonorafter in subjectconfirmationdata

Severity: low (CVSS 3.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-01-26 · updated 2026-06-17
Weakness: CWE-112

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 products

Red Hat build of Keycloak 26.4: all versions — fixed in 26.4-12, 26.4.10-1
Red Hat JBoss Enterprise Application Platform 8: all versions
Red Hat JBoss Enterprise Application Platform Expansion Pack: all versions
Red Hat Single Sign-On 7: all versions

How to fix

Upgrade to a fixed version: Red Hat build of Keycloak 26.4 26.4-12, 26.4.10-1. Check the vendor advisory for mitigations.

References

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