CVE-2023-6544Keycloak authorization bypass
What broke
Keycloak did not enforce an authorization check on a resource a lesser-privileged caller should not have reached. Red Hat shipped the fix in RHSA-2024:1868 (April 2024) with CVE-2023-6787 and CVE-2023-6717. The 2025 UMA first-resource bug is the same class returning.
Why it matters
An IdP that authenticates correctly and authorizes incorrectly is still an identity failure. Realm roles, client roles, and UMA policies are how Keycloak is access control for a lot of internal apps.
What to do
- Upgrade with the rest of the April 2024 Keycloak set. Do not cherry-pick the SAML CVE.
- Re-test fine-grained admin and UMA policies after the upgrade.
- Treat
realm-managementservice accounts as tier-zero.
After you patch
Patching closes the entry point. It does not remove access an attacker established through it.
- Revoke sessions and API tokens on the affected system rather than only resetting passwords.
- Audit accounts, tokens, and administrative changes made during the exposure window.
- Rotate credentials the system stored or could reach, including directory service accounts and integration keys. See secrets rotation.
- Treat the system as a pivot: whatever it could authenticate to is in scope until you have checked it.
Sources
- NVD: CVE-2023-6544
- Red Hat RHSA-2024:1868
Related identity CVEs
Related on Start with Identity
- CVEKeycloak accepts SAML from a disabled identity provider
A remote attacker can complete a broker login with a valid SAML response even after the SAML IdP is disabled in Keycloak. Unauthorized authentication via a cont
- CVEKeycloak Admin API auth bypass to custom attributes
Keycloak's Admin API let a caller read sensitive custom attributes they should not have seen (CWE-266). An authorization hole on the admin plane.
- CVEKeycloak client policy enforcement flaw
A 2026 Keycloak client-policy enforcement bug. Client policies are how you ban implicit flow, require PKCE, or force FAPI. If they do not fire, the realm's writ
- BlogAgent identity just got a protocol, which is the easy half
Okta shipped Agent SSO and got Cross App Access adopted into MCP the same month a GitHub issue was shown to reach CI secrets in Claude Code and Gemini CLI. The
- BlogAgentic AI Identity Is the Next Frontier (And Your IAM Stack Isn't Ready)
AI agents now act on behalf of users, call APIs, and chain tools together. They need identities, scopes, and audit trails, and almost no existing IAM stack was
- BlogCrowdStrike agrees to buy SGNL for 740 million dollars
The deal that opened 2026's consolidation wave. SGNL brings CAEP-based continuous access evaluation and just-in-time authorization to a Falcon identity business