CVE-2023-23928: Reason-Jose Project Reason-Jose

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

reason-jose is a JOSE implementation in ReasonML and OCaml.`Jose.Jws.validate` does not check HS256 signatures. This allows tampering of JWS header and payload data if the service does not perform additional checks. Such tampering could expose applications using reason-jose to authorization bypass. Applications relying on JWS claims assertion to enforce security boundaries may be vulnerable to privilege escalation. This issue has been patched in version 0.8.2.

Affected products

• Reason-Jose Project Reason-Jose: before 0.8.2 (fixed in 0.8.2)

Published 2023-02-01. Last modified 2026-06-17.