A flaw was found in the SAML 1.1 XML parsing logic of Keycloak, an open-source identity and access management solution. The issue occurs when the parser encounters unexpected elements within a security token's key information section, causing the processing thread to enter an infinite loop. An unauthenticated remote attacker could exploit this by sending specially crafted requests, leading to 100% CPU usage and a total denial of service that requires a server restart to resolve.
History

Thu, 05 Nov 2026 16:30:00 +0000

Type Values Removed Values Added
Description A flaw was found in the SAML 1.1 XML parsing logic of Keycloak, an open-source identity and access management solution. The issue occurs when the parser encounters unexpected elements within a security token's key information section, causing the processing thread to enter an infinite loop. An unauthenticated remote attacker could exploit this by sending specially crafted requests, leading to 100% CPU usage and a total denial of service that requires a server restart to resolve.
Title Keycloak-services: keycloak-services: unauthenticated cpu exhaustion via saml 1.1 keyinfo infinite loop
First Time appeared Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
Weaknesses CWE-835
CPEs cpe:/a:redhat:build_keycloak:
cpe:/a:redhat:red_hat_single_sign_on:7
Vendors & Products Redhat
Redhat build Keycloak
Redhat red Hat Single Sign On
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published: 2026-11-05T16:04:51.527Z

Updated: 2026-11-05T16:04:51.527Z

Reserved: 2026-10-08T12:39:57.410Z

Link: CVE-2026-107602

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-11-05T17:17:35.117

Modified: 2026-11-05T17:17:35.247

Link: CVE-2026-107602

cve-icon Redhat

No data.