Description
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.
Affected products
redhat: build of keycloak; redhat: jboss enterprise application platform expansion pack
References2
- access.redhat.com/security/cve/CVE-2026-18967 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2511604 Permissions Required
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: NVD
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 14 · as of 12 November 2026
- CWE
- CWE-294
Could this be exploited in your environment?
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