CVE-2026-82461

Description

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.

References

https://www.vulncheck.com/advisories/pac4j-oidc-before-6.5.6-privilege-escalation-via-unverified-keycloak-access-token

https://www.pac4j.org/blog/security-advisory-pac4j-core-oidc-saml.html

https://github.com/pac4j/pac4j/commit/2270c3ff70e93cc43831e75702acd5135531237e

https://github.com/pac4j/pac4j/blob/pac4j-parent-6.5.5/pac4j-oidc/src/main/java/org/pac4j/oidc/authorization/generator/KeycloakRolesAuthorizationGenerator.java

https://github.com/pac4j/pac4j

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4