# Info Leak

> Detect sensitive information leakage in web applications and APIs - exposed API keys, tokens, PII in HTML/JS, debug pages, source maps, .git directories, .env files, backup files, internal IPs, stack traces, and version strings. Use during reconnaissance to identify sensitive data exposed to attackers.

- Skill: `wufufu770/info-leak-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add wufufu770/info-leak-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/wufufu770/info-leak-2/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- License: Apache-2.0
- Author: wufufu770 (https://skillmd.com/u/wufufu770)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/wufufu770/info-leak-2

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## TL;DR

- **目的**：Detect sensitive information leakage in web applications and APIs
- **适用**：侦察阶段 + 全流程持续检查
- **输入**：目标 URL + 关注数据类型（API 密钥 / PII / 源码）
- **输出**：泄露位置清单 + 严重性分级 + 修复优先级
- **红线**：仅检测不利用；测试前确认数据已脱敏
- **关联**：上游：所有 hunt-* skill → 下游：reporting skill



## When to Use

- Target presents indicators of the vulnerability class this skill covers
- Fingerprint or recon indicates the relevant technology stack is in use
- Authorized testing scope covers the target endpoint or component
- Findings need to be validated through this skill's methodology

## When NOT to Use

- Target is clearly outside this skill's scope (refer to related skills)
- No authorization for testing
- Need a different category of testing (use related skills)
## Workflow

1. **Fingerprint** — Detect technology stack to find known leak patterns
2. **Static grep** — Search HTML/JS for API keys, tokens, emails
3. **Endpoint scan** — Try common paths (.git, .env, /backup, /config)
4. **Source map analysis** — Extract original source from .map files
5. **Error trigger** — Force errors to see stack traces
6. **Document** — Per-leak: type, severity, exploitation path



## Advanced Techniques

### Source Map Extraction
For JS applications with exposed .map files, use `sourcemapper` or `source-map-resolver` to reconstruct original source code and find hardcoded API keys.

### Git Directory Exposure
Even partial `.git/` exposure can be exploited with `git-dumper` to reconstruct the repository and find secrets, credentials, and internal documentation.

### Source Code Comments
Search for `// TODO: remove before prod`, `// FIXME: insecure`, and similar markers - they often indicate known security issues that weren't properly fixed.