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xxe

Hunt XML External Entity flaws in parsers and validate file read / SSRF impact with strict negative controls.

60

Quality

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SecuritybySnyk

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tessl review fix ./packages/decepticon/decepticon/skills/standard/analyst/xxe/SKILL.md
SKILL.md
Quality
Evals
Security

XXE Playbook

Find parser sinks

  • Java: DocumentBuilderFactory, SAXParserFactory, XMLInputFactory
  • Python: lxml.etree, xml.dom.minidom, xml.sax
  • .NET: XmlDocument, XDocument, XmlReader

Dangerous defaults

  • DTD enabled
  • External entities enabled
  • Network/file entity resolution enabled

Payloads

  • File read: entity to file:///etc/passwd
  • SSRF: entity to internal URL (metadata service, localhost admin)

Validation

  • Positive: parser output contains file content or internal response markers.
  • Negative: same XML without entity expansion must not leak content.
Repository
PurpleAILAB/Decepticon
Path

packages/decepticon/decepticon/skills/standard/analyst/xxe/SKILL.md

Commit

e34afba

Last updated
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