What is CVE-2026-44664?

CVE-2026-44664 is a medium-severity security vulnerability in fast-xml-builder (npm), affecting versions = 1.1.5. It is fixed in 1.1.6.

How severe is CVE-2026-44664?

CVE-2026-44664 has a CVSS score of 6.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of fast-xml-builder are affected by CVE-2026-44664?

fast-xml-builder (npm) versions = 1.1.5 is affected.

Is there a fix for CVE-2026-44664?

Yes. CVE-2026-44664 is fixed in 1.1.6. Upgrade to this version or later.

Is CVE-2026-44664 exploitable, and should I be worried?

Whether CVE-2026-44664 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether CVE-2026-44664 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

CVE-2026-44664 in fast-xml-builder | Intelligent Application Security

Q: How do I fix CVE-2026-44664?

Upgrade fast-xml-builder to 1.1.6 or later.

Summary

The fix for https://github.com/advisories/GHSA-gh4j-gqv2-49f6 in fast-xml-parser sanitizes -- sequences in XML comment content using .replace(/--/g, '- -'). This skip the values containing three consecutive dashes (e.g., --->...), allowing an attacker to break out of an XML comment and inject arbitrary XML/HTML content.

Workarounds

Check for the presence of 3 consecutive dashes externally in the property value used for comment tag.

Impact

Any application with comment property enabled allow attacker to inject malicious or unwanted code like JS script tag in the XML/HTML output.

CVE-2026-44664 has a CVSS score of 6.1 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.1.6); upgrading removes the vulnerable code path.

Affected versions

fast-xml-builder (= 1.1.5)

Security releases

fast-xml-builder → 1.1.6 (npm)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

See it in your environment

Remediation advice

Upgrade fast-xml-builder to 1.1.6 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

What is CVE-2026-44664? CVE-2026-44664 is a medium-severity security vulnerability in fast-xml-builder (npm), affecting versions = 1.1.5. It is fixed in 1.1.6.
How severe is CVE-2026-44664? CVE-2026-44664 has a CVSS score of 6.1 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which versions of fast-xml-builder are affected by CVE-2026-44664? fast-xml-builder (npm) versions = 1.1.5 is affected.
Is there a fix for CVE-2026-44664? Yes. CVE-2026-44664 is fixed in 1.1.6. Upgrade to this version or later.
Is CVE-2026-44664 exploitable, and should I be worried? Whether CVE-2026-44664 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether CVE-2026-44664 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix CVE-2026-44664? Upgrade fast-xml-builder to 1.1.6 or later.

Other vulnerabilities in fast-xml-builder

CVE-2026-44665