High severity · published Mar 27, 2026
CVE-2026-33891
Forge has Denial of Service via Infinite Loop in BigInteger.modInverse() with Zero Input
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
forge · digitalbazaar
< 1.4.0 · source: vendor, NVD
CO
Cluster Observability Operator 1.5.0 · Red Hat
All versions, or not specified · source: CISA
LS
Logging Subsystem for Red Hat OpenShift · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Build of Podman Desktop · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Developer Hub 1.8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Developer Hub 1.9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Fuse 7 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat build of Apicurio Registry 2 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33891
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33891
Patch
https://github.com/digitalbazaar/forge/commit/9bb8d67b99d17e4ebb5fd7596cd699e11f25d023
Exploit
https://github.com/digitalbazaar/forge/security/advisories/GHSA-5m6q-g25r-mvwx
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:13826
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:24761
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:24762
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:34342
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