offensive-api-security SKILL.md skillC

offensive-api-security from snailsploit/claude-red is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned
mdr add snailsploit/claude-red/offensive-api-security@git:20260825.1885f44

Pins git:20260825.1885f44 in mdr.lock. Pin the fingerprint instead.

Audit grade
C, 15 of 17 checks passed
Kind
SKILL.md skill
Repository
snailsploit/claude-red
Path
Skills/api/offensive-api-security/SKILL.md
Versions recorded
2
Latest version
git:20260825.1885f44, committed Aug 25, 2026
First version recorded
Aug 25, 2026
Size
19,822 bytes
Repository stars
10,442
License
MIT

Comprehensive API security testing methodology covering REST, gRPC, and WebSocket attack surfaces. Addresses the full OWASP API Security Top 10 2023 including BOLA/IDOR, broken authentication, excessive data exposure, rate limiting bypass, BFLA, mass assignment, SSRF, and security misconfiguration. Includes REST-specific attacks such as HTTP verb tampering, content-type switching, and parameter pollution. Covers gRPC exploitation through protobuf interception, reflection API enumeration, and…

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

# Offensive API Security Testing

You are conducting authorized security assessments against API-driven applications. This skill covers REST, gRPC, and WebSocket attack surfaces with emphasis on the OWASP API Security Top 10 2023. Every technique assumes you have written authorization and a defined scope. Your goal is to identify vulnerabilities that allow unauthorized data access, privilege escalation, or service disruption through API-layer attacks.

## Quick Workflow

1. Map the API surface: collect OpenAPI/Swagger specs, gRPC reflection output, and WebSocket endpoints.
2. Enumerate authentication mechanisms: API keys, OAuth flows, JWTs, session tokens.
3. Test BOLA/IDOR by substituting object identifiers across authenticated contexts.
4. Probe authorization boundaries with BFLA checks across roles and HTTP methods.
5. Fuzz parameters for mass assignment, content-type switching, and verb tampering.
6. Assess rate limiting and resource consumption controls.
7. Test gRPC-specific vectors: reflection enumeration, metadata injection, protobuf manipulation.
8. Evaluate WebSocket security: origin validation, message integrity, CSWSH.
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint
mdr add snailsploit/claude-red/offensive-api-security@sha256:c76a14cfc2e427d6

The line at the top of this page pins the label git:20260825.1885f44, 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.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_4rg5742uxb76gemz.svg)](https://markdownregistry.com/a/art_4rg5742uxb76gemz)

6 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 2 versions of this file, all committed on Aug 25, 2026.

versioncommittedcommitsizeaudit
git:20260825.1885f44 latest2026-08-25 1885f44 19,822 BC view · diff
git:20260825.8cffe5d2026-08-25 8cffe5d 24,137 BC view

Audit of the latest version

C  15 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
  • fail: No link to a raw IP address (matched: http://169.254.169.254)
  • fail: No script tag (matched: <script)
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (19822 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

Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.

Source

GitHub

snailsploit/claude-red · 10,442 stars · license MIT · pushed 2026-10-12 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_4rg5742uxb76gemz
GET https://markdownregistry.com/api/v1/resolve?ref=snailsploit/claude-red/offensive-api-security
GET https://markdownregistry.com/api/v1/blob/c76a14cfc2e427d64b769445de5d6ef233c10188c2aeee1ce3dc1631b8b1cd23

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.

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