OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). The AES GCM decryption routine incorrectly uses the Tag length from the actual Authentication Tag provided in the JWE. The spec says that a fixed length of 16 octets must be applied. Therefore this bug allows an attacker to provide a truncated Authentication Tag and to modify the JWE accordingly. Users should upgrade to a version >= 0.6.2.2. Users unable to upgrade should avoid using AES GCM encryption and replace it with another encryption algorithm (e.g. AES CBC).
datatracker.ietf.org/doc/html/rfc7518
github.com/OpenIDC/cjose/commit/7325e9a5e71e2fc0e350487ecac7d84acdf0ed5e
github.com/OpenIDC/cjose/releases/tag/v0.6.2.2
github.com/OpenIDC/cjose/security/advisories/GHSA-3rhg-3gf2-6xgj
lists.debian.org/debian-lts-announce/2023/08/msg00002.html
lists.fedoraproject.org/archives/list/[email protected]/message/DFWAPMYYVBO2U65HPYDTBEKNSXG4TP5C/
lists.fedoraproject.org/archives/list/[email protected]/message/LCQJXKDPCWCXB2V4JMQ3UWYJ4UIBPUW6/
lists.fedoraproject.org/archives/list/[email protected]/message/PTZHOVGY7AHGNMEY245HK4Q36AMA53AL/
www.debian.org/security/2023/dsa-5472