CVE-2026-82462

MediumCVSS 6.5

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

Summary

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.

Risk Assessment

The risk involves an attacker being able to create authenticated sessions without proper verification, potentially leading to account takeover or unauthorized access to protected resources.

Recommendation

It is recommended to upgrade pac4j-oidc to version 6.5.6 or later, which requires full token validation.

Other vulnerabilities in pac4j-oidc

CVE-2026-82461High
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.

Original NVD description (English source)

pac4j-oidc before 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.