fast-xml-parser has RangeError DoS Numeric Entities Bug_CVE-2026-25128

7.5 / 10

HIGH

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

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 4.3.6 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., `&#9999999;` or `&#xFFFFFF;`). This causes the parser to throw an uncaught exception, crashing any application that processes untrusted XML input. Version 5.3.4 fixes the issue.

Basic Information

ID CVE-2026-25128

Source GitHub_M

Published Jan 30, 2026 at 15:14

Modified Jan 30, 2026 at 15:40

Affected Product

Vendor NaturalIntelligence

Product fast-xml-parser

Version >= 4.3.6, < 5.3.4

Affected Versions NaturalIntelligence fast-xml-parser >= 4.3.6, < 5.3.4

CWE Classification

CWE-20 CWE-248

References

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    "published": "2026-01-30T15:14:58.244Z",
    "modified": "2026-01-30T15:40:55.259Z",
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    "references": "https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-37qj-frw5-hhjh\nhttps://github.com/NaturalIntelligence/fast-xml-parser/commit/4e387f61c4a5cef792f6a2f42467013290bf95dc\nhttps://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.3.4",
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