CVE-2026-18967

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.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 5.2

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-18967	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2511604	Permissions Required

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:redhat:build_of_keycloak:-::::-:::
	cpe:2.3:a:redhat:jboss_enterprise_application_platform_expansion_pack:-:::::::*

History

No history.

Information

Published : 2026-08-06 07:16

Updated : 2026-08-10 19:15

NVD link : CVE-2026-18967

Mitre link : CVE-2026-18967

CVE.ORG link : CVE-2026-18967

JSON object : View

Products Affected

redhat

build_of_keycloak
jboss_enterprise_application_platform_expansion_pack

CWE

CWE-294

Authentication Bypass by Capture-replay

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