Vulnerability Description
fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. In versions 5.0.9 through 5.3.3, a RangeError vulnerability exists in the numeric entity processing of fast-xml-parser when parsing XML with out-of-range entity code points (e.g., `�` or `�`). This causes the parser to throw an uncaught exception, crashing any application that processes untrusted XML input. Version 5.3.4 fixes the issue.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Naturalintelligence | Fast-Xml-Parser | >= 5.0.9, < 5.3.4 |
Related Weaknesses (CWE)
References
- https://github.com/NaturalIntelligence/fast-xml-parser/commit/4e387f61c4a5cef792Patch
- https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.3.4Release Notes
- https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-ExploitVendor Advisory
FAQ
What is CVE-2026-25128?
CVE-2026-25128 is a vulnerability with a CVSS score of 7.5 (HIGH). fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. In versions 5.0.9 through 5.3.3, a RangeError vulnerabi...
How severe is CVE-2026-25128?
CVE-2026-25128 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-25128?
Check the references section above for vendor advisories and patch information. Affected products include: Naturalintelligence Fast-Xml-Parser.