hunting-xxe-and-xml-parser-trust SKILL.md skillA
hunting-xxe-and-xml-parser-trust from unboundcompute/security-agent-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add unboundcompute/security-agent-skills/hunting-xxe-and-xml-parser-trust@git:20260903.6dac719Pins git:20260903.6dac719 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- unboundcompute/security-agent-skills
- Path
skills/hunting-xxe-and-xml-parser-trust/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260903.6dac719, committed Sep 3, 2026
- Size
- 9,517 bytes
- Repository stars
- 26
- License
- MIT
Hunt XML external entity injection and unsafe XML parser features where untrusted XML is parsed with document type definitions, external general or parameter entities, or XInclude enabled. Covers in-band file disclosure and server-side request forgery through external entities, blind out-of-band exfiltration through parameter entities, and denial of service through entity expansion. The XML often hides inside other formats: office documents, SVG images, SOAP calls, and identity assertions all…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Hunting XXE and XML parser trust: when the parser fetches what the document asks for An XML parser is dangerous when it honors the parts of the XML specification that let a document reach outside itself: a document type definition can declare external entities that the parser resolves by reading a local file or fetching a URL, parameter entities can drive that resolution even when the result is never reflected, and XInclude can pull in external content directly. Untrusted XML that reaches such a parser turns into local file disclosure, server-side request forgery including to internal and cloud-metadata endpoints, blind out-of-band exfiltration, and denial of service by recursive entity expansion. The XML is frequently not obvious: office documents, SVG images, SOAP envelopes, and federated identity assertions all carry XML into a parser. The one fact that governs everything is how the specific parser is configured. You find XXE by locating every XML parse of untrusted input and reading whether DTDs and external entities are enabled. ## When to use - A service parses XML from request bodies, file uploads, or federated messages. …
Read the whole file at its exact version.
How to install
mdr add unboundcompute/security-agent-skills/hunting-xxe-and-xml-parser-trust@sha256:af7f37983fa489a0The line at the top of this page pins the label git:20260903.6dac719, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_6ahjgeltfp3p2aop)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Sep 3, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (9517 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
unboundcompute/security-agent-skills · 26 stars · license MIT · pushed 2026-09-08 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_6ahjgeltfp3p2aop GET https://markdownregistry.com/api/v1/resolve?ref=unboundcompute/security-agent-skills/hunting-xxe-and-xml-parser-trust GET https://markdownregistry.com/api/v1/blob/af7f37983fa489a0cbdd6956db97f3913f4dc999e7440b053d25decb1500dbeb
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.