CVSS 4.0
6.9 mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NCVE-2026-82462
Medium (6.9). EPSS 0.2% chance of exploitation in the next 30 days.
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.
Severity
CVSS 3.1
6.5 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 9% of CVEs (scores of 2026-10-31)
- CWE
- CWE-345
- Published
- Modified
- Record from
- the NVD, synced
References
- 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