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 4.1.3 through 5.3.5, the XML parser can be forced to do an unlimited amount of entity expansion. With a very small XML input, it’s possible to make the parser spend seconds or even minutes processing a single request, effectively freezing the application. Version 5.3.6 fixes the issue. As a workaround, avoid using DOCTYPE parsing by `processEntities: false` option.
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Fri, 20 Feb 2026 12:15:00 +0000
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Naturalintelligence
Naturalintelligence fast-xml-parser |
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Naturalintelligence
Naturalintelligence fast-xml-parser |
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| 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 4.1.3 through 5.3.5, the XML parser can be forced to do an unlimited amount of entity expansion. With a very small XML input, it’s possible to make the parser spend seconds or even minutes processing a single request, effectively freezing the application. Version 5.3.6 fixes the issue. As a workaround, avoid using DOCTYPE parsing by `processEntities: false` option. | |
| Title | fast-xml-parser affected by DoS through entity expansion in DOCTYPE (no expansion limit) | |
| Weaknesses | CWE-776 | |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-02-19T19:40:55.842Z
Updated: 2026-02-19T21:21:49.452Z
Reserved: 2026-02-12T17:10:53.414Z
Link: CVE-2026-26278
Updated: 2026-02-19T20:58:41.932Z
Status : Awaiting Analysis
Published: 2026-02-19T20:25:43.717
Modified: 2026-02-20T13:49:47.623
Link: CVE-2026-26278