CVE-2026-18967
MEDIUMKeycloak-services: keycloak-services: saml onetimeuse assertion replay in idp-initiated broker flow
Title source: cnaDescription
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.
References (2)
Core 2
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry
x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-18967
Issue Tracking, X_Refsource_Redhat issue-tracking
x_refsource_redhat
RHBZ#2511604
https://bugzilla.redhat.com/show_bug.cgi?id=2511604
Scores
CVSS v3
6.4
EPSS
0.0014
EPSS Percentile
4.0%
Attack Vector
ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-294
Status
published
Products (3)
Red Hat/Red Hat Build of Keycloak
Red Hat/Red Hat JBoss Enterprise Application Platform Expansion Pack
Red Hat/Red Hat Single Sign-On 7
Published
Aug 06, 2026
Tracked Since
Aug 06, 2026