CVE-2026-82461

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/pac4j/pac4j
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/commit/2270c3ff70e93cc43831e75702acd5135531237e
https://www.pac4j.org/blog/security-advisory-pac4j-core-oidc-saml.html
https://www.vulncheck.com/advisories/pac4j-oidc-before-6.5.6-privilege-escalation-via-unverified-keycloak-access-token

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-29 17:17

Updated : 2026-09-10 19:54

NVD link : CVE-2026-82461

Mitre link : CVE-2026-82461

CVE.ORG link : CVE-2026-82461

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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