CVE-2026-33894

HIGH

Forge has signature forgery in RSA-PKCS due to ASN.1 extra field

Title source: cna
STIX 2.1

Description

Forge (also called `node-forge`) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, RSASSA PKCS#1 v1.5 signature verification accepts forged signatures for low public exponent keys (e=3). Attackers can forge signatures by stuffing “garbage” bytes within the ASN structure in order to construct a signature that passes verification, enabling Bleichenbacher style forgery. This issue is similar to CVE-2022-24771, but adds bytes in an addition field within the ASN structure, rather than outside of it. Additionally, forge does not validate that signatures include a minimum of 8 bytes of padding as defined by the specification, providing attackers additional space to construct Bleichenbacher forgeries. Version 1.4.0 patches the issue.

Scores

CVSS v3 7.5
EPSS 0.0004
EPSS Percentile 13.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-20 CWE-347
Status published
Products (2)
digitalbazaar/forge < 1.4.0 (2 CPE variants)
npm/node-forge 0 - 1.4.0npm
Published Mar 27, 2026
Tracked Since Mar 29, 2026