highVulnerability

GHSA-8r6m-32jq-jx6q

### Impact `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. An attacker can therefore insert additional DOCTYPE declarations to repeatedly reset maxTotalExpansions and maxExpandedLength during one parse operation. This allows a crafted XML document to exceed the configured entity-expansion limits and can cause excessive CPU use, event-loop blocking, memory exhaustion, and process termination. ### Workarounds - Manually check if multiple DOCTYPEs are not present in input contents - Update to v5.10.1 - Keep `processEntity` flag off

Properties

ghsa_id
GHSA-8r6m-32jq-jx6q
severity
high
summary
fast-xml-parser: Repeated DOCTYPE declarations reset entity expansion limits
cve_id
GHSA-8r6m-32jq-jx6q
is_ghsa_only
true
ghsa_published
2026-07-21T22:06:36Z
source_url
https://github.com/advisories/GHSA-8r6m-32jq-jx6q
ghsa_updated
2026-07-21T22:06:38Z

Related Entities (4)

VULNERABLE_TO (1)

[Software]npm/fast-xml-parser

AFFECTS (1)

[Software]npm/fast-xml-parser

HAS_WEAKNESS (1)

[Weakness]Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')

REPORTED_BY (1)

[Source]GitHub Advisory Database

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GHSA-8r6m-32jq-jx6q — Ninja Signal Threat Intelligence | Ninja Signal