CVE-2026-26278
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
19/02/2026
Last modified:
19/02/2026
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.
Impact
Base Score 3.x
7.50
Severity 3.x
HIGH