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CVE-2026-73569 (GCVE-0-2026-73569)

Vulnerability from cvelistv5 – Published: 2026-08-13 17:45 – Updated: 2026-08-13 18:40
VLAI
Title
fast-xml-parser: Repeated DOCTYPE declarations reset entity expansion limits
Summary
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.
Severity
8.7 (High)
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
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 18:39 UTC
CWE
  • CWE-776 - Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')
Assigner
References
Impacted products
Vendor Product Version CPE status
NaturalIntelligence fast-xml-parser Affected: >= 5.9.3, < 5.10.1
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.