CVE-2026-85393

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/advisories/GHSA-ppp5-5v6c-4jwp
https://github.com/digitalbazaar/forge
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/asn1.js
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/rsa.js
https://github.com/digitalbazaar/forge/issues/1149
https://www.vulncheck.com/advisories/node-forge-through-1.4.0-rsa-pkcs-1-1.5-signature-forgery-via-nested-digestalgorithm-padding
https://github.com/advisories/GHSA-ppp5-5v6c-4jwp

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-03 19:17

Updated : 2026-09-03 20:17

NVD link : CVE-2026-85393

Mitre link : CVE-2026-85393

CVE.ORG link : CVE-2026-85393

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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