CVE-2026-85393: Node forge Node-forge RSA PKCS#1 V1.5 Signature Vulnerability

HIGH
Advisory Identifier: GHSA-86w9-cpqp-85rv
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CVSS 7.5
CWE-347
Published
Advisory Summary

CVE-2026-85393 is a HIGH (CVSS 7.5) node-forge rsa pkcs#1 v1.5 signature vulnerability (CWE-347: Improper Verification of Cryptographic Signature) affecting Node forge libraries in the npm ecosystem. The issue involves node-forge rsa pkcs#1 v1.5 signature verification accepts extra nested digestalgorithm elements. Remediation is available in the latest vendor maintenance releases.

CVE-2026-85393 at a Glance

CVE Identifier CVE-2026-85393
GHSA Identifier GHSA-86w9-cpqp-85rv
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-347: Improper Verification of Cryptographic Signature
Affected Product Node forge
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-85393

To remediate this vulnerability, upgrade all affected Node forge dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

node-forge fixed: Latest secure release 
npm install node-forge@Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls node-forge

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-85393, inspect your project dependencies using npm:

npm ls node-forge

Analyze the terminal output to locate any version of Node forge in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The npm ls node-forge command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-347: Improper Verification of Cryptographic Signature, where the product does not verify, or incorrectly verifies, the cryptographic signature for data. In Node forge, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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.

CVE-2026-85393 Affected Node forge Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
node-forge
npm/node-forge
npm
≤ 1.4.0

References

NVD — CVE-2026-85393 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-85393
Node forge Source Repository REPOSITORY
https://github.com/digitalbazaar/forge/issues/1149
Node forge Source Repository REPOSITORY
https://github.com/digitalbazaar/forge/pull/1152
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-ppp5-5v6c-4jwp
Node forge Source Repository REPOSITORY
https://github.com/digitalbazaar/forge
Node forge Source Repository REPOSITORY
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/asn1.js
Node forge Source Repository REPOSITORY
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/rsa.js
www.vulncheck.com/advisories/node-for... WEB
https://www.vulncheck.com/advisories/node-forge-through-1.4.0-rsa-pkcs-1-1.5-signature-forgery-via-nested-digestalgorithm-padding

Frequently Asked Questions

What is CVE-2026-85393?
CVE-2026-85393 is a security vulnerability in Node forge involving node-forge RSA PKCS#1 v1.5 signature verification accepts extra nested DigestAlgorithm elements under CWE-347: Improper Verification of Cryptographic Signature.
Which Node forge versions are affected?
Affected versions include releases prior to current release patches across affected packages: node-forge.
What version fixes CVE-2026-85393?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is node-forge affected?
Yes, node-forge is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2026-85393?
CVE-2026-85393 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
What CWE is associated with CVE-2026-85393?
CVE-2026-85393 is classified under CWE-347: Improper Verification of Cryptographic Signature (The product does not verify, or incorrectly verifies, the cryptographic signature for data.).
How can I check npm dependencies for CVE-2026-85393?
Run the dependency tree command: 'npm ls node-forge'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-86w9-cpqp-85rv",
  "modified" : "2026-10-01T21:09:09Z",
  "published" : "2026-09-03T21:31:15Z",
  "aliases" : [ "CVE-2026-85393" ],
  "summary" : "node-forge RSA PKCS#1 v1.5 signature verification accepts extra nested DigestAlgorithm elements",
  "details" : "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.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "node-forge"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "1.4.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-85393"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/digitalbazaar/forge/issues/1149"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/digitalbazaar/forge/pull/1152"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-ppp5-5v6c-4jwp"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/digitalbazaar/forge"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/asn1.js"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/rsa.js"
  }, {
    "type" : "WEB",
    "url" : "https://www.vulncheck.com/advisories/node-forge-through-1.4.0-rsa-pkcs-1-1.5-signature-forgery-via-nested-digestalgorithm-padding"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-347" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-01T21:09:09Z",
    "nvd_published_at" : "2026-09-03T19:17:31Z"
  }
}