Vulnerability Description
get-jwks contains fetch utils for JWKS keys. In versions prior to 11.0.2, a vulnerability in get-jwks can lead to cache poisoning in the JWKS key-fetching mechanism. When the iss (issuer) claim is validated only after keys are retrieved from the cache, it is possible for cached keys from an unexpected issuer to be reused, resulting in a bypass of issuer validation. This design flaw enables a potential attack where a malicious actor crafts a pair of JWTs, the first one ensuring that a chosen public key is fetched and stored in the shared JWKS cache, and the second one leveraging that cached key to pass signature validation for a targeted iss value. The vulnerability will work only if the iss validation is done after the use of get-jwks for keys retrieval. This issue has been patched in version 11.0.2.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://github.com/nearform/get-jwks/commit/1706a177a80a1759fe68e3339dc5a219ce03
- https://github.com/nearform/get-jwks/security/advisories/GHSA-qc2q-qhf3-235m
FAQ
What is CVE-2025-59936?
CVE-2025-59936 is a vulnerability with a CVSS score of 9.4 (CRITICAL). get-jwks contains fetch utils for JWKS keys. In versions prior to 11.0.2, a vulnerability in get-jwks can lead to cache poisoning in the JWKS key-fetching mechanism. When the iss (issuer) claim is val...
How severe is CVE-2025-59936?
CVE-2025-59936 has been rated CRITICAL with a CVSS base score of 9.4/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2025-59936?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.