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Fencer Vulns
high 7.5

CVE-2026-33891 json

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

published 2026-03-26 7 mo ago modified 2026-10-26 13 d ago also EUVD-2026-16833 , GHSA-5m6q-g25r-mvwx

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 49%
public exploits
0
none known

Summary

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.

Patch / fix

  • npm node-forge 1.4.0
  • Red Hat Red Hat Ansible Automation Platform 2.5 for RHEL 8 0:2.5.20260422-3.el8ap
  • Red Hat Red Hat Ansible Automation Platform 2.5 for RHEL 9 0:2.5.20260422-3.el9ap
  • Red Hat Red Hat Ansible Automation Platform 2.6 for RHEL 9 0:2.6.9-1.el9ap
  • Red Hat Cluster Observability Operator 1.5.0 1782839279
  • Red Hat Red Hat Developer Hub 1.8 1776784286
  • Red Hat Red Hat Developer Hub 1.9 1777903262
  • receptor ansible automation platform 2.6 1.6.5-1.el10ap
  • receptor ansible automation platform inside 2.6, ansible automation platform inside 2.5, ansible automation platform developer 2.6 +3 more 1.6.5-1.el9ap
  • receptorctl ansible automation platform 2.6 1.6.5-1.el10ap
  • receptorctl ansible automation platform inside 2.6, ansible automation platform developer 2.6, ansible automation platform 2.6 1.6.5-1.el9ap
  • python3-click ansible automation platform developer 2.6, ansible automation platform 2.6 8.3.3-1.el10ap
  • python3.12-click ansible automation platform inside 2.6, ansible automation platform inside 2.5, ansible automation platform developer 2.6 +3 more 8.3.3-1.el9ap
  • python3.12-pillow ansible automation platform 2.6, ansible automation platform 2.5 12.2.0-1.el9ap
  • automation-controller ansible automation platform developer 2.6, ansible automation platform 2.6 4.7.12-1.el9ap

red hat advisories RHSA-2026:24762RHSA-2026:24761

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-33891 updated cvss 7.5

node-forge: node-forge: Denial of Service via infinite loop in BigInteger.modInverse()

  • Red Hat Logging Subsystem for Red Hat OpenShift openshift-logging/kibana6-rhel8, openshift-logging/elasticsearch6-rhel9, openshift-logging/logging-curator5-rhel9, openshift-logging/elasticsearch-proxy-rhel9, openshift-logging/elasticsearch-rhel9-operator, openshift-logging/elasticsearch-operator-bundle
    affected: workaround, no fix planned “Will not fix”
  • Red Hat build of Apicurio Registry 2 io.apicurio-apicurio-registry Red Hat Build of Podman Desktop podman-desktop-macos-1-0, podman-desktop-windows-1-0 Red Hat Enterprise Linux 10 grafana
    affected: workaround, no fix available
  • Red Hat Fuse 7 io.apicurio-apicurito, io.syndesis-syndesis-parent
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Cluster Observability Operator 1.5 cluster-observability-operator/logging-console-plugin-pf4-rhel9 1782839279
    fixed: vendor fix RHSA-2026:34342
  • Red Hat Ansible Automation Platform 2.5 for RHEL 8 automation-gateway-server 2.5.20260422-3.el8ap Red Hat Ansible Automation Platform 2.5 for RHEL 9 automation-gateway-server 2.5.20260422-3.el9ap
    fixed: vendor fix RHSA-2026:24761
  • Red Hat Ansible Automation Platform 2.6 for RHEL 9 automation-platform-ui 2.6.9-1.el9ap
    fixed: vendor fix RHSA-2026:24762
  • Red Hat Ceph Storage 9.2 rhceph/rhceph-9-rhel10 1790843527
    fixed: vendor fix RHSA-2026:86618
  • Red Hat Developer Hub 1.8 rhdh 1776784286
    fixed: vendor fix RHSA-2026:9742
show 8 more
  • Red Hat Developer Hub 1.9 rhdh 1777903262
    fixed: vendor fix RHSA-2026:13826
  • Red Hat Cluster Observability Operator 1.5 cluster-observability-operator/perses-rhel9 1782839109, cluster-observability-operator/thanos-rhel9 1782840280, cluster-observability-operator/korrel8r-rhel9 1782839157, cluster-observability-operator/prometheus-rhel9 1782840780, cluster-observability-operator/alertmanager-rhel9 1782840761, cluster-observability-operator/perses-rhel9-operator 1782839191, +18 more
    not affected: vulnerable code not present
  • Red Hat Cryostat 4 io.cryostat-cryostat
    not affected: component not present
  • Red Hat Ansible Automation Platform 2 automation-eda-controller Red Hat Ansible Automation Platform 2.5 for RHEL 8 receptor 1.6.5-1.el8ap, receptorctl 1.6.5-1.el8ap, automation-hub 4.10.15-1.el8ap, python3.12-click 8.3.3-1.el8ap, python3.12-pillow 12.2.0-1.el8ap, python3.12-pulpcore 3.49.61-1.el8ap, +12 more Red Hat Ansible Automation Platform 2.5 for RHEL 9 receptor 1.6.5-1.el9ap, receptorctl 1.6.5-1.el9ap, automation-hub 4.10.15-1.el9ap, python3.12-click 8.3.3-1.el9ap, python3.12-pillow 12.2.0-1.el9ap, python3.12-pulpcore 3.49.61-1.el9ap, +12 more Red Hat Ansible Automation Platform 2.6 for RHEL 9 receptor 1.6.5-1.el9ap, molecule 26.4.0-2.el9ap, receptorctl 1.6.5-1.el9ap, ansible-sign 0.1.5-1.el9ap, ansible-lint 26.4.0-1.el9ap, automation-hub 4.11.9-1.el9ap, +37 more Red Hat Ansible Automation Platform 2.6 for RHEL 10 receptor 1.6.5-1.el10ap, molecule 26.4.0-2.el10ap, receptorctl 1.6.5-1.el10ap, ansible-sign 0.1.5-1.el10ap, python-click 8.3.3-1.el10ap, ansible-lint 26.4.0-1.el10ap, +12 more Red Hat build of Apache Camel - HawtIO 4 io.hawt-project
    +1 more products
    Red Hat Ceph Storage 9.2 rhceph/alloy-rhel10 1790774976, rhceph/grafana-rhel10 1790774121, rhceph/keepalived-rhel10 1790842990, rhceph/oauth2-proxy-rhel10 1790774021, rhceph/snmp-notifier-rhel10 1790773439, rhceph/rhceph-haproxy-rhel10 1790846345
    not affected: vulnerable code not present
  • Red Hat Data Grid 8 org.infinispan-infinispan-console
    not affected: vulnerable code cannot be controlled by adversary
  • Red Hat Developer Hub 1.8 rhdh 1776783947, rhdh 1776787729 Red Hat Developer Hub 1.9 rhdh 1777902709, rhdh 1777909942 Red Hat Enterprise Linux 8 pcs, pcs-snmp
    not affected: vulnerable code not present
  • Red Hat Enterprise Linux 9 pcs, grafana, pcs-snmp, grafana-selinux
    not affected: component not present
  • Red Hat Process Automation 7 org.uberfire-uberfire-parent Red Hat Quay 3 quay/quay-rhel8
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
7 mo ago

Exploit prediction

0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/digitalbazaar/forge/security/advisories/GHSA-5m6q-g25r-mvwx referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
npm node-forge
<1.4.0
1.4.0

Affected products

  • digitalbazaar forge
  • Red Hat Red Hat Ansible Automation Platform 2.5 for RHEL 8
  • Red Hat Red Hat Ansible Automation Platform 2.5 for RHEL 9
  • Red Hat Red Hat Ansible Automation Platform 2.6 for RHEL 9
  • Red Hat Cluster Observability Operator 1.5.0
  • Red Hat Red Hat Developer Hub 1.8
  • Red Hat Red Hat Developer Hub 1.9
  • Red Hat Cryostat 4
  • Red Hat Logging Subsystem for Red Hat OpenShift
  • Red Hat Red Hat Ansible Automation Platform 2
  • Red Hat Red Hat build of Apache Camel - HawtIO 4
  • Red Hat Red Hat build of Apicurio Registry 2
  • Red Hat Red Hat Build of Podman Desktop
  • Red Hat Red Hat Data Grid 8
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Fuse 7
  • Red Hat Red Hat Process Automation 7
  • Red Hat Red Hat Quay 3

Classification

Weakness
  • CWE-835 Loop with Unreachable Exit Condition
  • CWE-606 Unchecked Input for Loop Condition

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.