CVE-2026-82461

HighCVSS 8.1

Published: 29/08/2026(UTC)Translated: 29/08/2026(UTC)NVD NIST

Summary

pac4j-oidc before version 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.

Risk Assessment

The risk includes the possibility of privilege escalation and unauthorized access to administrative resources, which could lead to full application compromise.

Recommendation

It is recommended to update pac4j-oidc to version 6.5.6 or later, which properly verifies access tokens, and to implement additional security controls for roles.

Other vulnerabilities in pac4j-oidc

CVE-2026-82462Medium
pac4j-oidc before version 6.5.6 accepts OIDC callbacks carrying only an access token without authorization code or ID token validation. Attackers can substitute access tokens minted for other clients to create authenticated sessions without proper issuer, audience, nonce, or subject verification.

Original NVD description (English source)

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.