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Not in CISA KEV

CVE-2026-41674 — @xmldom/xmldom

Fix: xmldom/xmldom@372008f

CVE-2026-41674 is a CWE-91 vulnerability in @xmldom/xmldom. A fix is available for @xmldom/xmldom — see the affected versions and patch details below.

xmldom: XML injection through unvalidated DocumentType serialization

Also known asGHSA-f6ww-3ggp-fr8h
Published
May 7, 2026
Updated
Sep 12, 2026
Affected
3 pkgs
Patched
2 / 3
Exploits
None indexed
Exploitation data as of Sep 21, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

  • CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41674.

EPSS Exploitation Probability

via FIRST.org ↗
0.5%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs43th percentile — riskier than 43% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

3 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

1Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream
@xmldom/xmldomnpm
37.1Mdownloads / week
xmldomnpm
1.3Mdownloads / week

Description

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. In @xmldom/xmldom prior to versions 0.9.10 and 0.8.13 and xmldom version 0.6.0 and prior, the package serializes DocumentType node fields (internalSubset, publicId, systemId) verbatim without any escaping or validation. When these fields are set programmatically to attacker-controlled strings, XMLSerializer.serializeToString can produce output where the DOCTYPE declaration is terminated early and arbitrary markup appears outside it. This issue has been patched in versions @xmldom/xmldom versions 0.9.10 and 0.8.13.

Affected Packages

3 total 2 fixed
EcosystemPackageVulnerable rangeFix
📦npm@xmldom/xmldomall versions0.8.13npm install @xmldom/xmldom@0.8.13
📦npm@xmldom/xmldom≥ 0.9.0&&< 0.9.100.9.10npm install @xmldom/xmldom@0.9.10
📦npmxmldomall versionsNo fix

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @xmldom/xmldom, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update @xmldom/xmldom to 0.8.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41674 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41674 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2026-41674. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

ProductFixed inAdvisory
Red Hat Developer Hub 1.8rhdh/rhdh-hub-rhel9:1779841586RHSA-2026:21338
Red Hat Developer Hub 1.9rhdh/rhdh-hub-rhel9:1781187342RHSA-2026:26234
Red Hat OpenShift Container Platform 4.20openshift4/ose-agent-installer-ui-rhel9:1779864090RHSA-2026:21703
Red Hat OpenShift Container Platform 4.21openshift4/ose-agent-installer-ui-rhel9:1779252093RHSA-2026:20034

Frequently Asked Questions

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) `DOMParser` and `XMLSerializer` module. In @xmldom/xmldom prior to versions 0.9.10 and 0.8.13 and xmldom version 0.6.0 and prior, the package serializes DocumentType node fields (internalSubset, publicId, systemId) verbatim without any escaping or validation. When these fields are set programmatically to attacker-controlled strings, XMLSerializer.serializeToString can produce output where the DOCTYPE declaration is terminated early and arbitrary markup appears outside it. This issue has been patched in versions @xmldom/xmldo
O3 Security · Impact-Aware SCA

Is CVE-2026-41674 in your dependencies?

O3 Security finds CVE-2026-41674 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works
CVE-2026-41674: @xmldom/xmldom | O3 Security