CVE-2025-65945

HIGH

auth0/node-jws <4.0.0 - Improper Signature Verification

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2025-65945. PoCs published by jedisct1, adminlove520.

AI-analyzed exploit summary This PoC demonstrates a signature verification bypass in the `node-jws` library, allowing attackers to forge valid JWTs when HMAC secrets are derived from user-controlled data. The exploit leverages an empty secret to bypass validation when a non-existent key ID is provided.

Description

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.

Exploits (2)

nomisec WORKING POC 5 stars
by jedisct1 · poc
https://github.com/jedisct1/CVE-2025-65945-poc

This PoC demonstrates a signature verification bypass in the `node-jws` library, allowing attackers to forge valid JWTs when HMAC secrets are derived from user-controlled data. The exploit leverages an empty secret to bypass validation when a non-existent key ID is provided.

Classification
Working Poc 100%
Attack Type
Auth Bypass
Complexity
Trivial
Reliability
Reliable
Target: node-jws <= 3.2.2 and 4.0.0
No auth needed
Prerequisites: Vulnerable version of node-jws installed · Server-side code that looks up secrets based on JWT headers
devstral-2 · analyzed Feb 16, 2026 Full analysis →
github WORKING POC 2 stars
by adminlove520 · pythonpoc
https://github.com/adminlove520/CVE-Poc_All_in_One/tree/main/2025/CVE-2025-65945

This repository contains a functional exploit for CVE-2025-65945, demonstrating a signature verification bypass in the `node-jws` library. The exploit forges a JWT with an empty secret, bypassing authentication when the server fails to validate the secret properly.

Classification
Working Poc 100%
Attack Type
Auth Bypass
Complexity
Trivial
Reliability
Reliable
Target: node-jws (versions <= 3.2.2 and 4.0.0)
No auth needed
Prerequisites: node-jws library installed (vulnerable version) · Bun or Node.js runtime
devstral-2 · analyzed Feb 27, 2026 Full analysis →

Scores

CVSS v3 7.5
EPSS 0.0002
EPSS Percentile 3.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-347
Status published
Products (3)
auth0/node-jws 4.0.0
auth0/node-jws < 3.2.2
npm/jws 0 - 3.2.3npm
Published Dec 04, 2025
Tracked Since Feb 18, 2026