CVE-2026-26278 (GCVE-0-2026-26278)

Vulnerability from cvelistv5 – Published: 2026-02-19 19:40 – Updated: 2026-07-02 12:04
VLAI?
Title
fast-xml-parser affected by DoS through entity expansion in DOCTYPE (no expansion limit)
Summary
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.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-776 - Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')
Assigner
References
Impacted products
Vendor Product Version
NaturalIntelligence fast-xml-parser Affected: >= 5.0.0, < 5.3.6
Affected: >= 4.1.3, < 4.5.4
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