CVE-2026-27942

HIGH7.5

fast-xml-parser has stack overflow in XMLBuilder with preserveOrder

Published Feb 26, 2026

Modified 2 months ago

Details

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. Prior to version 5.3.8, the application crashes with stack overflow when user use XML builder with preserveOrder:true. Version 5.3.8 fixes the issue. As a workaround, use XML builder with preserveOrder:false or check the input data before passing to builder.

References

WEB

https://github.com/NaturalIntelligence/fast-xml-parser/commit/c13a961910f14986295dd28484eee830fa1a0e8a

WEB

https://github.com/NaturalIntelligence/fast-xml-parser/pull/791

WEB

https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-fj3w-jwp8-x2g3

ADVISORY

https://www.cve.org/CVERecord?id=CVE-2026-27942

CVSS Analysis

CVSS v4.0

2.7