Vulnerability in Pac4j

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 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-82462?
CVE-2026-82462 is a medium-severity vulnerability in Pac4j, classified under Insufficient Verification of Data Authenticity. CVSS score: 6.5/10. Published 2026-08-29.
How severe is CVE-2026-82462?
Medium severity. CVSS v3 base score is 6.5 out of 10.