CVE-2026-18218

Vendor solution

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Red Hat statement

The Red Hat Product Security team has assessed the severity of this vulnerability as Moderate, given that exploitation requires a specific pre-existing realm configuration and the possession of valid tokens issued within a specific timeframe. Successful exploitation allows an attacker to continue using revoked tokens for refresh, introspection, and UserInfo requests. The vulnerability's root cause is a logic error in the TokenManager.NotBeforeCheck function that fails to correctly enforce client-specific revocation policies when a realm-level policy is also present. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Red Hat mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.