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 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.
Published: 2026-01-30
Score: 7.5 High
EPSS: < 1% Very Low
KEV: No
Impact: Denial of Service via unhandled RangeError in XML parsing
Action: Patch
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-37qj-frw5-hhjh fast-xml-parser has RangeError DoS Numeric Entities Bug
History

Fri, 27 Feb 2026 20:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:naturalintelligence:fast-xml-parser:*:*:*:*:*:*:*:*

Wed, 11 Feb 2026 19:00:00 +0000

Type Values Removed Values Added
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. 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., `&#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.

Tue, 03 Feb 2026 15:00:00 +0000

Type Values Removed Values Added
First Time appeared Naturalintelligence
Naturalintelligence fast-xml-parser
Vendors & Products Naturalintelligence
Naturalintelligence fast-xml-parser

Sat, 31 Jan 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Fri, 30 Jan 2026 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 30 Jan 2026 15:30:00 +0000

Type Values Removed Values Added
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.
Title fast-xml-parser has RangeError DoS Numeric Entities Bug
Weaknesses CWE-20
CWE-248
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Subscriptions

Naturalintelligence Fast-xml-parser
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-02-11T18:38:40.192Z

Reserved: 2026-01-29T14:03:42.540Z

Link: CVE-2026-25128

cve-icon Vulnrichment

Updated: 2026-01-30T15:40:48.124Z

cve-icon NVD

Status : Analyzed

Published: 2026-01-30T16:16:14.123

Modified: 2026-02-27T20:22:44.700

Link: CVE-2026-25128

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-01-30T15:14:58Z

Links: CVE-2026-25128 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-04-18T01:15:05Z

Weaknesses