hunt-xxe

Locate XML parsing entry points and validate XXE file disclosure, OOB callbacks, or SSRF.

Updated Aug 27, 2026
One-click install
npx skills add https://github.com/AKasem1/claude-bug-bounty --skill hunt-xxe
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: hunt-xxe
Source: https://github.com/AKasem1/claude-bug-bounty/tree/main/skills/hunt-xxe
Command: npx skills add https://github.com/AKasem1/claude-bug-bounty --skill hunt-xxe

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

XXE vulnerabilities can let attackers coerce a vulnerable XML parser into reading sensitive files, triggering out-of-band callbacks, or reaching internal services via SSRF.

Core Features & Use Cases

  • Hunt for XXE entry points: Map XML-related endpoints by paths, headers, and client-side parsing hints, then focus testing where the target actually consumes XML.
  • Validate impact quickly: Run in-band payloads for file disclosure, escalate to blind out-of-band (DNS/HTTP) when reflection is blocked, and then confirm SSRF to internal destinations such as cloud instance metadata.
  • Produce a defensible report chain: Document the exploit path (file read → SSRF → internal access) and apply reproducibility and severity gates so findings are triage-ready.
  • Use cases: XML APIs, SOAP/WSDL services, SAML/SSO endpoints, and server-side document processing (DOCX/XLSX/SVG and similar) where XML parsing may be hidden inside uploads or conversions.

Quick Start

Use the hunt-xxe skill against the target and verify an XXE impact path by testing a known XML endpoint and attempting a short in-band entity payload for file disclosure or, if blocked, a blind OOB callback.

Frequently Asked Questions about hunt-xxe

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I find and validate XXE vulnerabilities in XML APIs?▼

To find and validate XXE vulnerabilities, locate XML parsing entry points in XML APIs and test for external entity expansion leading to file disclosure, out-of-band callbacks, or SSRF to internal services.

What is the best way to test for blind XXE when in-band reflection is blocked?▼

When in-band reflection is blocked, escalate blind XXE testing using out-of-band DNS or HTTP callbacks to confirm external entity processing and validate impact via OOB exfiltration channels.

Can I use this approach to hunt for XXE in SAML SSO and SOAP services?▼

Yes, this approach targets XML-heavy backends including SAML/SSO endpoints with XML-based assertions and SOAP/WSDL services to identify and validate external entity vulnerabilities.

Does XXE testing work against server-side document processing uploads like DOCX or SVG?▼

Yes, XXE testing works against server-side document processing or uploads that re-parse XML containers like DOCX, XLSX, and SVG files where XML parsing may be hidden inside conversions.

How do I escalate XXE file read to SSRF and access cloud metadata?▼

After confirming XXE file read, pivot by attempting SSRF to internal destinations such as cloud instance metadata endpoints, documenting the exploit path from file read to internal access.

How do I prepare a defensible bug bounty report for an XXE vulnerability?▼

Produce a defensible bug bounty report by documenting the full exploit path from file read to SSRF and applying reproducibility and severity gates so findings are triage-ready.