CVE-2021-41106 Information

Description

JWT is a library to work with JSON Web Token and JSON Web Signature. Prior to versions 3.4.6 4.0.4 and 4.1.5 users of HMAC-based algorithms (HS256 HS384 and HS512) combined with Lcobucci\JWT\Signer\Key\LocalFileReference as key are having their tokens issued/validated using the file path as hashing key - instead of the contents. The HMAC hashing functions take any string as input and since users can issue and validate tokens users are lead to believe that everything works properly. Versions 3.4.6 4.0.4 and 4.1.5 have been patched to always load the file contents deprecated the Lcobucci\JWT\Signer\Key\LocalFileReference and suggest Lcobucci\JWT\Signer\Key\InMemory as the alternative. As a workaround use Lcobucci\JWT\Signer\Key\InMemory instead of Lcobucci\JWT\Signer\Key\LocalFileReference to create the instances of one’s keys.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Reference

https://github.com/lcobucci/jwt/security/advisories/GHSA-7322-jrq4-x5hf https://github.com/lcobucci/jwt/commit/c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01c https://github.com/lcobucci/jwt/commit/8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

3.3