CVE-2026-27942lowCWE-120

CVE-2026-27942: low-severity vulnerability in NaturalIntelligence fast-xml-parser

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

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8Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 2.7epss 0.5%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U
Affected products
NaturalIntelligence · fast-xml-parser
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