Is CVE-2026-85393 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-85393 being exploited in the wild.

How severe is CVE-2026-85393?

High severity, with a CVSS score of 7.5, published 3 September 2026.

Is there a fix for CVE-2026-85393?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-85393 attacked?

It is attacked over the network.

Am I affected by CVE-2026-85393?

Check whether you run 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.

CVE-2026-85393: node-forge RSA signature forgery via ASN.1 parsing bypass

CVE-2026-85393 · Severity: high · CVSS 7.5 · Published 2026-09-03

node-forge is a JavaScript cryptography library used to verify digital signatures on documents and communications. A flaw in RSA signature verification allows attackers to forge valid signatures for arbitrary messages when using low-exponent RSA keys (exponent=3), bypassing security checks that would be caught by standard cryptographic implementations like OpenSSL. This could enable unauthorized access to signed documents or impersonation of legitimate signers.

Technologies: node-forge (npm). Vendors: npm.

Quick answers

Is CVE-2026-85393 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-85393 being exploited in the wild.
How severe is CVE-2026-85393?: High severity, with a CVSS score of 7.5, published 3 September 2026.
Which products and versions are affected?: node-forge (npm) <= 1.4.0.
Is there a fix for CVE-2026-85393?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-85393 attacked?: It is attacked over the network.
Am I affected by CVE-2026-85393?: Check whether you run 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.

Technical details

The vulnerability exists in node-forge's RSA PKCS#1 v1.5 signature verification logic (lib/rsa.js). The _parseAllDigestBytes option guarantees all ASN.1 bytes are parsed but does not enforce that the parsed structure matches the minimal canonical DigestInfo shape required by RFC 8017. Attackers can embed attacker-controlled additional ASN.1 content (garbage bytes) within the DigestAlgorithm sequence to construct forged signatures that pass forge verification but fail OpenSSL verification. Additionally, forge does not validate the minimum 8 bytes of padding (PS) specified in PKCS#1 v1.5, further reducing the difficulty of constructing Bleichenbacher-style forgeries. The issue is triggered when verifying signatures with default scheme (RSASSA-PKCS1-v1_5) on low-exponent RSA keys; no user interaction or authentication is required.

Affected products

Digital Bazaar node-forge through 1.4.0

Identifiers

CVE-2026-85393
GHSA-86w9-cpqp-85rv

Timeline

2026-09-03: disclosed

References

https://github.com/digitalbazaar/forge

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