hunt-subdomain
Hunting skill for subdomain takeover vulnerabilities. Includes modern provider fingerprints — Microsoft Azure DevOps `cloudapp.azure.com` regional-pool re-issue (1-click OAuth ATO via wildcard `reply_to`, Binary Security), Zendesk help-desk takeover → email interception → password reset chain (0xprial writeup), Vercel `cname.vercel-dns.com` deleted-project takeover, plus general Fastly CDN service re-attach and S3 dangling-bucket cookie-scope techniques. Use when hunting subdomain takeover — emphasis on ATO-chain primitives (OAuth `redirect_uri`, cookie-domain, email DNS).
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Critical
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Security
2 findings: 2 critical severity. Installing this skill is not recommended: please review these findings carefully if you do intend to do so.
E005: Suspicious download URL detected in skill instructions.
What this means
Detected a suspicious URL in the skill instructions that could lead the agent to download and execute malicious scripts or binaries. This includes links to executables from untrusted sources, typosquatting of official packages, URL shorteners that obscure the destination, and personal file hosting services.
Why it was flagged
There are no direct executable/download links, but several entries (legacy.target.com OAuth callback, feeds.visualstudio.com endpoint and the generic subdomain placeholders) are high-risk subdomain/OAuth takeover vectors that could be claimed to host attacker-controlled content or phishing payloads that deliver malware.
E006: Malicious code pattern detected in skill scripts.
What this means
Detected high-risk code patterns in the skill content — including its prompts, tool definitions, and resources — such as data exfiltration, backdoors, remote code execution, credential theft, system compromise, supply chain attacks, and obfuscation techniques.
Why it was flagged
This document is an explicit offensive how‑to for subdomain takeovers and escalation chains (OAuth token theft, session fixation, CSP/CORS abuse, email/SF/MX/DKIM takeover), enabling credential theft, phishing, and large‑scale exfiltration — high malicious risk.
- Repository
- elementalsouls/Claude-BugHunter
- Commit
6b9c96e
- Audited
- Security analysis
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