# CVE-2026-73569

## Summary

- **CVE ID:** CVE-2026-73569
- **Severity:** HIGH
- **CVSS Score:** 8.7 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-776
- **Published:** Aug 13, 2026
- **Last Modified:** Aug 13, 2026

## Description

fast-xml-parser allows users to process XML from JS object without C/C++ based libraries or callbacks. From 5.9.3 until 5.10.1, src/xmlparser/OrderedObjParser.js processes multiple DOCTYPE declarations within a single XML document and passes each declaration's entities through addInputEntities(). addInputEntities() resets maxTotalExpansions and maxExpandedLength every time it is called, allowing additional DOCTYPE declarations to repeatedly reset the configured entity-expansion limits during one parse operation. A crafted XML document can then cause excessive CPU use, event-loop blocking, memory exhaustion, and process termination. This issue is fixed in version 5.10.1.

## Affected Products

- NaturalIntelligence — fast-xml-parser (>= 5.9.3, < 5.10.1)

## References

- [CNA](https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-8r6m-32jq-jx6q)
- [CNA](https://github.com/NaturalIntelligence/fast-xml-parser/commit/4e546e03987662de5495d050b5fba26bea65383f)
- [CNA](https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.10.1)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.37%
- **EPSS Percentile:** 30.5

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-11._