Vulnerability 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 Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Lcobucci | Jwt | >= 3.4.0, < 3.4.6 |
Related Weaknesses (CWE)
References
- https://github.com/lcobucci/jwt/commit/8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73PatchThird Party Advisory
- https://github.com/lcobucci/jwt/commit/c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01cPatchThird Party Advisory
- https://github.com/lcobucci/jwt/security/advisories/GHSA-7322-jrq4-x5hfPatchThird Party Advisory
- https://github.com/lcobucci/jwt/commit/8175de5b841fbe3fd97d2d49b3fc15c4ecb39a73PatchThird Party Advisory
- https://github.com/lcobucci/jwt/commit/c45bb8b961a8e742d8f6b88ef5ff1bd5cca5d01cPatchThird Party Advisory
- https://github.com/lcobucci/jwt/security/advisories/GHSA-7322-jrq4-x5hfPatchThird Party Advisory
FAQ
What is CVE-2021-41106?
CVE-2021-41106 is a vulnerability with a CVSS score of 4.4 (MEDIUM). 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\Sig...
How severe is CVE-2021-41106?
CVE-2021-41106 has been rated MEDIUM with a CVSS base score of 4.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2021-41106?
Check the references section above for vendor advisories and patch information. Affected products include: Lcobucci Jwt.