CVE-2026-18967 (GCVE-0-2026-18967)

Vulnerability from cvelistv5 – Published: 2026-08-06 05:33 – Updated: 2026-08-06 17:31
VLAI
Title
Keycloak-services: keycloak-services: saml onetimeuse assertion replay in idp-initiated broker flow
Summary
A flaw was found in the SAML broker component of Keycloak, an identity and access management solution. When configured as a SAML broker using the IdP-Initiated flow, Keycloak fails to enforce the OneTimeUse condition in SAML assertions. This allows an attacker who captures a valid, unused assertion to replay it multiple times. Successful exploitation could allow an attacker to hijack a user's session and gain unauthorized access to the system as that user.
Severity
6.4 (Medium)
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-06 17:25 UTC
CWE
  • CWE-294 - Authentication Bypass by Capture-replay
Assigner
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-18967 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2511604 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-07-31 14:42
Credits
Red Hat would like to thank Lidor Vasker for reporting this issue.
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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