CVE-2026-82461: PAC4J

High severity, CVSS 8.1. EPSS: 0.3% chance of exploitation in the next 30 days.

pac4j-oidc before 6.5.6 fails to verify access token signatures, issuers, audiences, or expiry when extracting Keycloak realm and client roles. Attackers can forge access tokens with administrative roles paired with valid ID tokens to bypass authorization checks in applications relying on pac4j role validation.

Affected products

• PAC4J PAC4J: before 6.5.6 (fixed in 6.5.6)

Published 2026-08-29. Last modified 2026-09-10.