CVE-2026-33891

Forge has Denial of Service via Infinite Loop in BigInteger.modInverse() with Zero Input

Forge (also called `node-forge`) is a native implementation of Transport Layer Security in JavaScript. Prior to version 1.4.0, a Denial of Service (DoS) vulnerability exists in the node-forge library due to an infinite loop in the BigInteger.modInverse() function (inherited from the bundled jsbn library). When modInverse() is called with a zero value as input, the internal Extended Euclidean Algorithm enters an unreachable exit condition, causing the process to hang indefinitely and consume 100% CPU. Version 1.4.0 patches the issue.

Affected

digitalbazaar · forge

CVSS v3.1 CNA

7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

0.90% chance of exploitation in the next 30 days, 59th percentile

Published

2026-03-27

Updated

2026-09-04

Proof-of-concept exploits (1)

• advisories/GHSA-5m6q-g25r-mvwx

Security advisories

• digitalbazaar/forge/security/advisories/GHSA-5m6q-g25r-mvwx
• digitalbazaar/forge/commit/9bb8d67b99d17e4ebb5fd7596cd699e11f25d023

References

• CVE Record
• NVD entry