---
id: wiki-2026-0508-secrets-detection
title: Secrets Detection
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Credential Scanning, Leaked Secrets, Git Secret Scanning]
duplicate_of: none
source_trust_level: A
confidence_score: 0.9
verification_status: applied
tags: [security, secrets, gitleaks, trufflehog, devsecops]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: Go
  framework: gitleaks
---

# Secrets Detection

## 매 한 줄
> **"매 secret 의 leak 은 git history 의 forever — 매 prevention(pre-commit) > detection(CI) > remediation(rotate + rewrite history)"**. 매 origin 은 2014 GitHub 의 AWS key 대량 leak; 매 modern state 는 gitleaks/trufflehog v3 (entropy + verifier), GitHub Push Protection, AI-aided context analysis (Claude Opus 4.7 으로 매 false positive triage).

## 매 핵심

### 매 detection 의 3 layer
- **Pre-commit (local)**: gitleaks pre-commit hook — 매 push 전 차단.
- **CI (PR)**: gitleaks/trufflehog GitHub Action — 매 PR diff scan.
- **Org-wide (continuous)**: GitHub Advanced Security secret scanning, GitGuardian, 매 historical scan.

### 매 detection 기법
- **Regex patterns**: AWS `AKIA[0-9A-Z]{16}`, GitHub `ghp_[A-Za-z0-9]{36}`.
- **Entropy analysis**: Shannon entropy > 4.5 base64-like.
- **Verification**: 매 detected key 를 actual API call 로 verify (live or revoked).
- **AI context analysis**: 매 LLM 으로 매 surrounding code + filename → false positive triage.

### 매 응용
1. Pre-commit gate (developer machine).
2. CI/CD PR check.
3. Org-wide historical audit.
4. Incident response (breach detected → rotate all).

## 💻 패턴

### 매 gitleaks pre-commit hook
```yaml
# .pre-commit-config.yaml
repos:
  - repo: https://github.com/gitleaks/gitleaks
    rev: v8.21.0
    hooks:
      - id: gitleaks
```

```bash
$ pre-commit install
$ git commit -m "feat: add api"
# gitleaks........Failed
# leak: aws-access-token at config/dev.env:3
```

### 매 gitleaks custom config (매 corp tokens)
```toml
# .gitleaks.toml
[extend]
useDefault = true

[[rules]]
id = "acme-internal-token"
description = "Acme internal API token"
regex = '''ACME_[A-Z0-9]{32}'''
keywords = ["acme_"]
entropy = 3.5

[[rules]]
id = "anthropic-api-key"
description = "Anthropic API key"
regex = '''sk-ant-[a-zA-Z0-9-_]{95,}'''
keywords = ["sk-ant-"]

[allowlist]
description = "test fixtures"
paths = [
  '''(.*?)tests/fixtures/.*''',
  '''(.*?)\.example\..*''',
]
```

### 매 GitHub Action (PR scan)
```yaml
# .github/workflows/secrets-scan.yml
name: Secrets Scan
on: [pull_request]

jobs:
  gitleaks:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # 매 full history 필요
      - uses: gitleaks/gitleaks-action@v2
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GITLEAKS_LICENSE: ${{ secrets.GITLEAKS_LICENSE }}
```

### 매 trufflehog v3 (with verification, 매 live key 만 alert)
```bash
# 매 git history 전체 scan, 매 verified live key 만
$ trufflehog git file://. --only-verified --json | jq .

# 매 GitHub org scan
$ trufflehog github --org=acme --token=$GH_PAT --only-verified

# 매 Docker image scan
$ trufflehog docker --image=acme/api:latest --only-verified
```

### 매 leaked key remediation (매 4-step)
```bash
# 1. 매 ROTATE first (매 코드 수정 전!) — 매 leak 시 attacker timer 시작
aws iam create-access-key --user-name svc-deploy
aws iam delete-access-key --access-key-id AKIA... --user-name svc-deploy

# 2. 매 history rewrite (BFG, 매 git filter-repo 보다 빠름)
bfg --replace-text passwords.txt repo.git
cd repo.git && git reflog expire --expire=now --all && git gc --prune=now --aggressive

# 3. 매 force push (매 collaborator 들에게 reclone 공지)
git push --force-with-lease

# 4. 매 audit logs — 매 attacker 가 이미 사용했는지
aws cloudtrail lookup-events --lookup-attributes \
  AttributeKey=AccessKeyId,AttributeValue=AKIA...
```

### 매 AI-aided false-positive triage (Claude Opus 4.7)
```python
import anthropic
client = anthropic.Anthropic()

def triage(finding):
    """gitleaks finding -> {is_real_secret, severity, action}"""
    prompt = f"""You are a security engineer. Decide if this is a real secret leak.

Finding:
  File: {finding['file']}
  Line: {finding['line']}
  Match: {finding['match']}
  Context (5 lines before/after):
{finding['context']}

Output JSON:
  is_real_secret: bool
  reason: str
  severity: low|medium|high|critical
  action: rotate|ignore|investigate
"""
    msg = client.messages.create(
        model="claude-opus-4-7",
        max_tokens=512,
        messages=[{"role": "user", "content": prompt}],
    )
    return msg.content[0].text
```

### 매 GitHub Push Protection (매 enable, free for public)
```bash
# 매 org-level: Settings → Code security → Push protection: Enabled
# 매 push 시 GitHub 가 server-side block — 매 partner pattern 매 200+ provider
gh api -X PATCH orgs/acme \
  -F secret_scanning_push_protection_enabled_for_new_repositories=true
```

### 매 Doppler/Infisical (매 secret manager — 매 prevention root cause)
```bash
# 매 .env 의 X — 매 secret manager 에서 inject
$ doppler run -- python app.py
# 매 process env 에 inject, 매 disk 에 닿지 않음
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| 매 dev workstation | gitleaks pre-commit hook |
| 매 PR gate | gitleaks/trufflehog Action |
| 매 GitHub.com hosted | Push Protection enable |
| 매 large org historical | trufflehog --only-verified org-scan |
| 매 false-positive 많음 | Claude Opus 4.7 triage layer |
| 매 root-cause prevention | Doppler/Infisical, 매 .env 폐기 |

**기본값**: pre-commit (gitleaks) + CI (gitleaks Action) + GitHub Push Protection + Doppler.

## 🔗 Graph
- 부모: [[Application Security]] · [[CI_CD 파이프라인 및 IDE 통합 보안|DevSecOps]]
- 변형: [[Gitleaks]]
- Adjacent: [[Key Rotation]]

## 🤖 LLM 활용
**언제**: 매 finding triage (매 false positive vs real). 매 git history 의 narrative incident report.
**언제 X**: 매 detection 자체 — 매 deterministic regex/entropy 가 더 빠르고 cheap. 매 LLM 의 latency + cost 매 inline 부적절.

## ❌ 안티패턴
- **".env in repo"**: 매 매 the most common leak vector. 매 secret manager.
- **Commit-then-rotate skip**: 매 rotate skip — 매 history forever.
- **`.gitignore` rely**: 매 already-committed file 은 ignore 영향 X.
- **Force-push without coord**: 매 collaborator 의 reflog 에 leak 잔존.
- **Public-key panic**: 매 pub key 는 leak 의 X — 매 알고 commit.

## 🧪 검증 / 중복
- Verified (gitleaks docs v8.21, GitHub secret scanning docs 2026, OWASP Secrets Management Cheat Sheet).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — gitleaks + trufflehog + Push Protection + Claude triage |