CVE-2021-41106

File reference keys leads to incorrect hashes on HMAC algorithms

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.

Category

4.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.03%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: lcobucci jwt
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-41106?
CVE-2021-41106 has been scored as a medium severity vulnerability.
How to fix CVE-2021-41106?
To fix CVE-2021-41106, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-41106 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-41106 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41106?
CVE-2021-41106 affects lcobucci jwt.
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