CVE-2026-82462

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

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/credentials/extractor/OidcCredentialsExtractor.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-authentication-bypass-via-access-token-substitution

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-29 17:17

Updated : 2026-09-10 19:54

NVD link : CVE-2026-82462

Mitre link : CVE-2026-82462

CVE.ORG link : CVE-2026-82462

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

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