CVE-2026-25128 HIGH

CVE-2026-25128: fast-xml-parser has RangeError DoS Numeric Entities Bug

Vendor Naturalintelligence
Product fast-xml-parser
Weakness CWE-20 · Input validation
Published January 30, 2026
Last update February 11, 2026

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

January 30, 2026 CVE published
February 11, 2026 Record updated