CVE-2023-37464
cjose: AES GCM decryption uses the Tag length from the actual Authentication Tag provided in the JWE
Severity
ImportantRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 14, 2023
Updated · November 22, 2025
Description
A vulnerability was found in cjose. The 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 JSON Web Encryption (JWE). A fixed length of 16 octets must be applied. This flaw allows an attacker to provide a truncated Authentication Tag and modify the JWE.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Users unable to upgrade should avoid using AES GCM encryption and replace it with another encryption algorithm, such as AES CBC.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE-327 · Use of a Broken or Risky Cryptographic Algorithm