CVE-2026-33895 Forge has signature forgery in Ed25519 due to missing S > L check
Attackers can forge Ed25519 signatures to bypass authentication or authorization checks in applications using the Forge library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33895?
CVE-2026-33895 is a high-severity vulnerability in digitalbazaar forge, published on 27 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-347
Which versions are affected by CVE-2026-33895?
2 open source packages ship an affected version, including node-forge. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
node-forge npm | All versions | 1.4.0 |
node-forge npm | All versions | 1.4.0 |
Products include Digitalbazaar Forge.
How do I fix CVE-2026-33895?
Upgrade node-forge to 1.4.0 or later.
Is CVE-2026-33895 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33895 exists.
Other vulnerabilities in digitalbazaar forge
Sources
Also known as CLEANSTART-2026-ER79648, CLEANSTART-2026-PF59420, CLEANSTART-2026-WM82942, GHSA-q67f-28xg-22rw, MINI-276x-g45r-j6cx, MINI-48q6-4j7p-67xc and 19 more.