hunt-captcha-bypass
Hunt CAPTCHA Bypass — 6 distinct patterns: (1) CAPTCHA field simply omitted from the request (server-side validation absent), (2) CAPTCHA token replayed from a solved challenge (no single-use enforcement), (3) CAPTCHA response accepted on a different endpoint than it was solved on (no binding to action/session), (4) static or predictable CAPTCHA values accepted (e.g. '0', 'null', empty string), (5) audio/accessibility CAPTCHA trivially solvable programmatically, (6) CAPTCHA only enforced after N failures (first N requests bypass it). Detection: intercept a successful form submission, remove the CAPTCHA field entirely, replay — if it still succeeds, server-side validation is absent. Medium severity standalone; High when it removes the only rate-limit gate protecting a login, registration, or payment endpoint.
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tessl review fix ./skills/hunt-captcha-bypass/SKILL.mdE004: Prompt injection detected in skill instructions.
What this means
Detected a prompt injection in the skill instructions. The skill contains hidden or deceptive instructions that fall outside its stated purpose and attempt to override the agent’s safety guidelines or intended behavior.
Why it was flagged
This document gives explicit, actionable instructions to bypass CAPTCHA protections (omit fields, replay tokens, use concurrency) enabling automated abuse such as brute-force, account farming, and other attacks.
W007: Insecure credential handling detected in skill instructions.
What this means
The skill handles credentials insecurely by requiring the agent to include secret values verbatim in its generated output. This exposes credentials in the agent’s context and conversation history, creating a risk of data exfiltration.
Why it was flagged
The skill explicitly instructs capturing a live CAPTCHA token ("g-recaptcha-response") and replaying the exact token value in subsequent requests, which requires the LLM/agent to handle and output secret token values verbatim (exfiltration risk).
W011: Third-party content exposure detected (indirect prompt injection risk).
What this means
The skill exposes the agent to untrusted, user-generated content from public third-party sources, creating a risk of indirect prompt injection. This includes browsing arbitrary URLs, reading social media posts or forum comments, and analyzing content from unknown websites.
Why it was flagged
SKILL.md defines an autonomous testing workflow that directly instructs sending free-form HTTP form fields (e.g., omitting/replaying CAPTCHA inputs) to a target CAPTCHA-protected endpoint, so outsider-authored text can be ingested as part of the crafted requests.
- Repository
- elementalsouls/Claude-BugHunter
- Commit
d4b54e1
- Audited
- Security analysis
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