Description
Forge (also called `node-forge`) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, Ed25519 signature verification accepts forged non-canonical signatures where the scalar S is not reduced modulo the group order (`S >= L`). A valid signature and its `S + L` variant both verify in forge, while Node.js `crypto.verify` (OpenSSL-backed) rejects the `S + L` variant, as defined by the specification. This class of signature malleability has been exploited in practice to bypass authentication and authorization logic (see CVE-2026-25793, CVE-2022-35961). Applications relying on signature uniqueness (i.e., dedup by signature bytes, replay tracking, signed-object canonicalization checks) may be bypassed. Version 1.4.0 patches the issue.
Problem types
CWE-347: Improper Verification of Cryptographic Signature
Product status
References
github.com/.../forge/security/advisories/GHSA-q67f-28xg-22rw
github.com/.../forge/security/advisories/GHSA-q67f-28xg-22rw
github.com/...ommit/bdecf11571c9f1a487cc0fe72fe78ff6dfa96b85
datatracker.ietf.org/doc/html/rfc8032