High severity · published Sep 3, 2026
CVE-2026-85393
node-forge through 1.4.0 RSA PKCS#1 v1.5 Signature Forgery via Nested DigestAlgorithm Padding
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
forge · digitalbazaar
through 1.4.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-85393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-85393
github.com
https://github.com/advisories/GHSA-ppp5-5v6c-4jwp
github.com
https://github.com/digitalbazaar/forge
github.com
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/asn1.js
github.com
https://github.com/digitalbazaar/forge/blob/v1.4.0/lib/rsa.js
github.com
https://github.com/digitalbazaar/forge/issues/1149
www.vulncheck.com
https://www.vulncheck.com/advisories/node-forge-through-1.4.0-rsa-pkcs-1-1.5-signature-forgery-via-nested-digestalgorithm-padding
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