CVE-2026-27942

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/NaturalIntelligence/fast-xml-parser/commit/c13a961910f14986295dd28484eee830fa1a0e8a	Patch
https://github.com/NaturalIntelligence/fast-xml-parser/pull/791	Issue Tracking Patch
https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-fj3w-jwp8-x2g3	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:naturalintelligence:fast-xml-parser::::::::
	cpe:2.3:a:naturalintelligence:fast-xml-parser::::::::

History

No history.

Information

Published : 2026-02-26 02:16

Updated : 2026-03-02 14:54

NVD link : CVE-2026-27942

Mitre link : CVE-2026-27942

CVE.ORG link : CVE-2026-27942

JSON object : View

Products Affected

naturalintelligence

fast-xml-parser

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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