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hunt-mfa-bypass

Hunt MFA / 2FA bypass — 7 distinct patterns. (1) MFA not enforced on sensitive endpoints (password change, email change accept without MFA challenge), (2) MFA-step skip via direct navigation to post-login URL, (3) MFA-token replay (same code accepted twice), (4) brute-force the 6-digit OTP without rate limit (10^6 attempts at server speed), (5) race condition on OTP validation, (6) recovery-code dump via /api/me, (7) backup factor downgrade (SMS factor with no rate limit). Plus the chain: cookie theft + password oracle + no step-up = ATO without MFA challenge. Detection: trace auth flow in Burp, find every state transition, check if MFA is middleware-gated vs per-endpoint, check OTP entropy and rate limit on OTP-validate. Validate: attacker session reaching post-MFA state. Use when hunting auth bypass, MFA flows, chaining primitives toward ATO.

68

Quality

82%

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SecuritybySnyk

Critical

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SKILL.md
Quality
Evals
Security

Security

2 findings: 1 critical severity, 1 high severity. Installing this skill is not recommended: please review these findings carefully if you do intend to do so.

Critical

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 contains explicit, actionable instructions and tooling to bypass MFA, brute-force/replay OTPs, exfiltrate cookies/backup codes, and perform race/response-manipulation attacks that enable account takeover and other abuse.

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High

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 instructs the agent to embed session cookie values (e.g., YOUR_SESSION, PRE_MFA_SESSION) directly into curl/HTTP requests and code, which requires the LLM to handle and output secret/session tokens verbatim.

Repository
elementalsouls/Claude-BugHunter
Audited
Security analysis
Snyk

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