Vulnerability Description
fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. From 5.9.3 until 5.10.1, src/xmlparser/OrderedObjParser.js processes multiple DOCTYPE declarations within a single XML document and passes each declaration's entities through addInputEntities(). addInputEntities() resets maxTotalExpansions and maxExpandedLength every time it is called, allowing additional DOCTYPE declarations to repeatedly reset the configured entity-expansion limits during one parse operation. A crafted XML document can then cause excessive CPU use, event-loop blocking, memory exhaustion, and process termination. This issue is fixed in version 5.10.1.
Related Weaknesses (CWE)
References
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/4e546e03987662de54
- https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.10.1
- https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-
FAQ
What is CVE-2026-73569?
CVE-2026-73569 is a documented vulnerability. fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. From 5.9.3 until 5.10.1, src/xmlparser/OrderedObjParser.js processes multiple DOCTYPE declaration...
How severe is CVE-2026-73569?
CVSS scoring is not yet available for CVE-2026-73569. Check NVD for updates.
Is there a patch for CVE-2026-73569?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.