CVE-2026-33895: Digital Bazaar Forge signature malleability in Ed25519

CVE-2026-33895 · Severity: high · CVSS 7.5 · Published 2026-03-27

Forge (node-forge) is a widely used JavaScript library for implementing security protocols like TLS and digital signatures. A flaw in its signature verification process allows attackers to create multiple valid-looking signatures for the same data. This can be used to bypass security checks in applications that rely on unique signatures to prevent replay attacks or to verify the identity of users and systems.

Technologies: Digital Bazaar Forge, node-forge (npm). Vendors: Digital Bazaar, npm.

Quick answers

Is CVE-2026-33895 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-33895 being exploited in the wild.
How severe is CVE-2026-33895?
High severity, with a CVSS score of 7.5, published 27 March 2026.
Which products and versions are affected?
Digital Bazaar Forge < 1.4.0; node-forge (npm) SEMVER:introduced=0,fixed=1.4.0.
Is there a fix for CVE-2026-33895?
Yes. node-forge (npm): upgrade to 1.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-33895 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-33895?
Check whether you run Digital Bazaar Forge or node-forge (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • node-forge (npm): upgrade to 1.4.0 or later
    npm install node-forge@1.4.0

Technical details

The Forge library (node-forge) prior to version 1.4.0 fails to properly validate Ed25519 signatures according to RFC 8032 specifications. Specifically, the verification logic does not check if the scalar S is reduced modulo the group order L (S < L). This allows for signature malleability, where an attacker can take a valid signature and produce a different but still 'valid' variant (S + L). This vulnerability can be exploited to bypass deduplication logic, replay tracking, or authentication systems that assume signature uniqueness. The issue is resolved in version 1.4.0 by adding the necessary canonicality checks.

Affected products

  • Digital Bazaar forge < 1.4.0

Identifiers

  • CVE-2026-33895
  • GHSA-q67f-28xg-22rw

Timeline

  • 2026-03-20: other: Initial patch authored
  • 2026-03-24: patched: Patch committed to repository
  • 2026-03-27: disclosed: CVE published

References

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