Description
A flaw was found in the SAML XML processing component of Keycloak, an open-source identity and access management solution. The issue occurs when the server parses XML documents containing excessively long dateTime or duration values. Because these strings are not properly validated before processing, the XML parser consumes excessive CPU time. An unauthenticated remote attacker can exploit this by sending specially crafted SAML requests to the server, leading to high CPU utilization and a denial of service for all users.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.6 | — | — |
| Red Hat | Red Hat build of Keycloak 26.6.8 | — | — |
| Red Hat | Red Hat Single Sign-On 7 | — | — |
Advisories 1
- WID-SEC-2026-4375 Keycloak: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 11, 2026
References
- RHSA-2026:95761 vendor-advisory
- RHSA-2026:95762 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-107123 vdb-entry
- RHBZ#2547297 issue-tracking