---
id: CVE-2026-85393
title: >-
  node-forge through 1.4.0 fails to validate element count in nested
  DigestAlgorithm sequences during RSA PKCS#1 v1.5 signature verification
summary: >-
  node-forge through 1.4.0 fails to validate element count in nested
  DigestAlgorithm sequences during RSA PKCS#1 v1.5 signature verification.
  Attackers can embed garbage bytes inside the DigestAlgorithm sequence to forge
  valid signatures f…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-347
published: '2026-09-03'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T20:43:32.537'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-85393'
references:
  - url: 'https://github.com/advisories/GHSA-ppp5-5v6c-4jwp'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/digitalbazaar/forge'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/asn1.js'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/rsa.js'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/digitalbazaar/forge/issues/1149'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/node-forge-through-1.4.0-rsa-pkcs-1-1.5-signature-forgery-via-nested-digestalgorithm-padding
    label: disclosure@vulncheck.com
  - url: 'https://github.com/advisories/GHSA-ppp5-5v6c-4jwp'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00326
epssPercentile: 0.22953
ingestedAt: '2026-09-24T20:51:40.241Z'
---

## Overview

node-forge through 1.4.0 fails to validate element count in nested DigestAlgorithm sequences during RSA PKCS#1 v1.5 signature verification. Attackers can embed garbage bytes inside the DigestAlgorithm sequence to forge valid signatures for arbitrary messages using low-exponent RSA keys. This is an incomplete fix for CVE-2026-33894.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.