Description
fast-xml-parser processes multiple “DOCTYPE” declarations within a single XML document. Each declaration passes its entities to @nodable/entities through addInputEntities().
addInputEntities() resets the entity expansion counters every time it is called.
Recommendation
Update the fast-xml-parser package to the latest compatible version. Followings are version details:
- Affected version(s): >= 5.9.3, < 5.10.1
- Patched version(s): 5.10.1
References
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Start a free scanRelated Issues
- Entity Expansion Limits Bypassed When Set to Zero Due to JavaScript Falsy Evaluation in fast-xml-parser - CVE-2026-33349
- fast-xml-parser affected by DoS through entity expansion in DOCTYPE (no expansion limit) - CVE-2026-26278
- fast-xml-parser affected by numeric entity expansion bypassing all entity expansion limits (incomplete fix for CVE-2026- - CVE-2026-33036
- fast-xml-parser has an entity encoding bypass via regex injection in DOCTYPE entity names - CVE-2026-25896
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See something that needs correcting? Let us knowUpdated August 13, 2026