node-jws vulnerability

auth0/node-jws is a JSON Web Signature implementation for Node.js. In versions 3.2.2 and earlier and version 4.0.0, auth0/node-jws has an improper signature verification vulnerability when using the HS256 algorithm under specific conditions. Applications are affected when they use the jws.createVerify() function for HMAC algorithms and use user-provided data from the JSON Web Signature protected header or payload in HMAC secret lookup routines, which can allow attackers to bypass signature verification. This issue has been patched in versions 3.2.3 and 4.0.1.

Published 4 Dec 2025Updated 18 Oct 20262 sources
CVSS 7.5

What happened

auth0/node-jws is a JSON Web Signature implementation for Node.js. In versions 3.2.2 and earlier and version 4.0.0, auth0/node-jws has an improper signature verification vulnerability when using the HS256 algorithm under specific conditions. Applications are affected when they use the jws.createVerify() function for HMAC algorithms and use user-provided data from the JSON Web Signature protected header or payload in HMAC secret lookup routines, which can allow attackers to bypass signature verification. This issue has been patched in versions 3.2.3 and 4.0.1.

Affected versions

node-jws: < 3.2.3; >= 4.0.0, <= 4.0.1 Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.