CVE-2021-32796 is a medium-severity (CVSS 5.3) CWE-116 vulnerability in xmldom. A fix is available for xmldom — see the affected versions and patch details below.
Misinterpretation of malicious XML input
EPSS Exploitation Probability
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.
How urgent is this, really
CVE-2021-32796 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
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.
xmldomnpm@xmldom/xmldomnpmDescription
Impact
xmldom versions 0.6.0 and older do not correctly escape special characters when serializing elements removed from their ancestor. This may lead to unexpected syntactic changes during XML processing in some downstream applications.
Patches
Update to one of the fixed versions of @xmldom/xmldom (>=0.7.0)
See issue #271 for the status of publishing xmldom to npm or join #270 for Q&A/discussion until it's resolved.
Workarounds
Downstream applications can validate the input and reject the maliciously crafted documents.
References
Similar to this one reported on the Go standard library:
- https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities/
- https://mattermost.com/blog/securing-xml-implementations-across-the-web/
For more information
If you have any questions or comments about this advisory:
- Open an issue in
xmldom/xmldom - Email us: send an email to all addresses that are shown by
npm owner ls @xmldom/xmldom
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | xmldom | all versions | No fix |
| 📦npm | @xmldom/xmldom | all versions | 0.7.0npm install @xmldom/xmldom@0.7.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for xmldom, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
No patched version of xmldom has shipped for CVE-2021-32796 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2021-32796 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-32796. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-32796 in your dependencies?
O3 Security finds CVE-2021-32796 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.