CVE Tools
Sign in

CVE-2026-33895

Forge has signature forgery in Ed25519 due to missing S > L check

Published: Mar 27, 2026Updated: Jul 15, 2026 Sources: CVE List NVDCWE-347
7.5HIGH
NVD MITRE
EPSS Score
0.5%
Top 57.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-347

Affected Products

digitalbazaar
commercialaka digitalbazaar/forge
forgeLibrary
Security Products / pki-crypto

Exploitability

Official Patch Available
Is your org exposed to CVE-2026-33895?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://datatracker.ietf.org/doc/html/rfc8032#section-8.4
datatracker.ietf.org
https://github.com/digitalbazaar/forge/commit/bdecf11571c9f1a487cc0fe72fe78ff6dfa96b85
github.com
https://github.com/digitalbazaar/forge/security/advisories/GHSA-q67f-28xg-22rw
github.com
and 7 more references View all →
News mentions
1

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2026-33895 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows