hunt-source-leak – Coding skill for AI agents

HUNT-SOURCE-LEAK — Source Code & Build Artifact Leakage

Crown Jewel Targets

Source map exposing TypeScript source = see all API routes, auth logic, secrets. Swagger/OpenAPI JSON = complete API surface map.

Highest-value findings:

• .js.map source maps — reconstruct full TypeScript/ES6 source code → find hardcoded API keys, internal endpoints, auth logic bypasses
• swagger.json / openapi.json — complete REST API specification with all endpoints, parameters, auth schemes, and internal route names
• .env / .env.production — APP_KEY, DB_PASSWORD, API_KEY, SECRET_KEY in plaintext
• .git/ exposure — git clone the entire source history → all past hardcoded secrets
• asset-manifest.json / _next/static/ — all JS bundle paths → systematic source map discovery
• build-info / info.json — git commit hash, build timestamp, dependency versions → CVE targeting

---

Pitfalls (Read Before Probes)

1. Fake Source Maps — HTML Serving as .map

Some SPAs (Angular/React on nginx) serve their index.html for any unhandled route, including .js.map URLs. The URL ends in .map and returns HTTP 200, but the content is HTML — not JSON.

Detect before processing:

# First 80 bytes tell the story
head -c 80 /tmp/map_file
# "<!DOCTYPE" or "<html" = faux map (SPA serving HTML)
# "{" or ")))}" = real source map

python3 -c "
with open('/tmp/map_file') as f:
    d = f.read()
if d.strip().startswith('{'): print('Real source map')
elif '<!DOCTYPE' in d or '<html' in d: print('FAUX — SPA serving HTML')
else: print(f'Unknown, first 80b: {repr(d[:80])}')
"

Fallback: Download raw JS bundles and grep directly (Phase 8).

2. BusyBox / Alpine grep -P

On minimal containers (Alpine Linux), grep -P (Perl-compatible regex) is NOT available. This affects Phase 2 Step 2, Phase 7, and swagger extraction. Use Python3 re instead:

# Instead of: grep -Eo 'pattern' file
python3 -c "import sys, re; print(*(re.findall(r'pattern', sys.stdin.read())), sep='\n')" < file

3. crt.sh Rate Limiting

The crt.sh API rate-limits aggressively — queries too close together return empty JSON/timeouts. Wait 10-15s between queries. Use &limit=20 to reduce response size: https://crt.sh/?q=%25.TARGET&output=json&limit=20

---

Phase 1 — Quick Wins (Run First)

# These 10 requests take <30 seconds and often yield Critical findings
for PATH in \
  "/.env" \
  "/.env.production" \
  "/.env.local" \
  "/.git/HEAD" \
  "/swagger.json" \
  "/api/swagger.json" \
  "/v1/swagger.json" \
  "/openapi.json" \
  "/api/openapi.json" \
  "/api-docs"; do
  STATUS=$(curl --max-time 30 --connect-timeout 10 -s -o /tmp/sl_test -w "%{http_code}" "https://$TARGET$PATH")
  if [ "$STATUS" = "200" ]; then
    echo "[+] HIT: https://$TARGET$PATH"
    head -5 /tmp/sl_test
    echo "---"
  fi
done

---

Phase 2 — Source Map Discovery

See references/react-api-extraction.md for the full React SPA source-map API extraction pipeline.

# Step 1: Get asset manifest to find all JS bundle paths
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/asset-manifest.json" | python3 -m json.tool 2>/dev/null
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/static/js/main.*.js" 2>/dev/null | head -3

# Next.js
BUILD_ID=$(curl --max-time 30 --connect-timeout 10 -s https://$TARGET/ | grep -Eo '"buildId":"\K[^"]+')
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/_next/static/$BUILD_ID/_buildManifest.js" | head -5

# Step 2: For each JS bundle, check for source map reference at end of file
for JS_URL in $(curl --max-time 30 --connect-timeout 10 -s https://$TARGET/ | grep -Eo 'src="[^"]*\.js"' | sed 's/src="//;s/"//'); do
  LAST_LINE=$(curl --max-time 30 --connect-timeout 10 -s "https://$TARGET$JS_URL" | tail -1)
  echo "$LAST_LINE" | grep -q "sourceMappingURL" && echo "[+] Source map: $JS_URL"
done

# Step 3: Download and reconstruct source from .map files
JS_URL="https://$TARGET/static/js/main.abc123.js"
MAP_URL="${JS_URL}.map"
curl --max-time 30 --connect-timeout 10 -s "$MAP_URL" | python3 -c "
import sys, json, os
data = json.load(sys.stdin)
sources = data.get('sources', [])
contents = data.get('sourcesContent', [])
for i, (src, content) in enumerate(zip(sources, contents)):
    if content:
        path = '/tmp/sourcemap_extract/' + src.replace('../','').replace('./',''). replace('webpack://','')
        os.makedirs(os.path.dirname(path), exist_ok=True)
        with open(path, 'w') as f:
            f.write(content)
        print(f'[+] Extracted: {src}')
"

# Step 4: Grep extracted source for secrets
grep -r "API_KEY\|SECRET\|PASSWORD\|TOKEN\|PRIVATE" /tmp/sourcemap_extract/ 2>/dev/null
grep -r "process\.env\." /tmp/sourcemap_extract/ 2>/dev/null | grep -v "NEXT_PUBLIC_" | head -20
grep -r "http://internal\|localhost\|127\.0\.0\.1\|10\.\|172\.\|192\.168" /tmp/sourcemap_extract/ 2>/dev/null | head -20

---

Phase 3 — Swagger / OpenAPI Discovery

# Common paths
SWAGGER_PATHS=(
  "/swagger.json" "/swagger.yaml" "/swagger/"
  "/api/swagger.json" "/api/swagger.yaml"
  "/v1/swagger.json" "/v2/swagger.json" "/v3/swagger.json"
  "/openapi.json" "/openapi.yaml"
  "/api/openapi.json" "/api-docs" "/api-docs.json"
  "/api/v1/swagger.json" "/api/v2/swagger.json"
  "/rest/swagger.json" "/rest/api-docs"
  "/.well-known/openapi.json"
  "/graphql/schema.json"
)

for PATH in "${SWAGGER_PATHS[@]}"; do
  STATUS=$(curl --max-time 30 --connect-timeout 10 -s -o /tmp/swagger_test -w "%{http_code}" "https://$TARGET$PATH")
  if [ "$STATUS" = "200" ]; then
    echo "[+] Found: https://$TARGET$PATH"
    # Extract all API paths from swagger
    python3 -c "
import sys, json
try:
    d = json.load(open('/tmp/swagger_test'))
    paths = list(d.get('paths', {}).keys())
    print(f'Endpoints: {len(paths)}')
    print('\n'.join(sorted(paths)))
except: pass
" | head -50
  fi
done

---

Phase 4 — .git Exposure

# Check if .git directory is accessible
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/.git/HEAD" | grep -q "ref:" && echo "[+] .git exposed!"

# If exposed, reconstruct repo
# Tool: git-dumper
pip3 install git-dumper
git-dumper "https://$TARGET/.git/" /tmp/dumped-repo/

# Grep for secrets in all git history
cd /tmp/dumped-repo && \
  git log --all --oneline 2>/dev/null | head -20
  git grep -i "password\|secret\|api_key\|token" $(git rev-list --all) 2>/dev/null | head -30

# trufflehog on git history
trufflehog git file:///tmp/dumped-repo/ 2>/dev/null | head -50

---

Phase 5 — Forgotten Files & Debug Endpoints

# Build artifacts and debug files
DEBUG_PATHS=(
  "/build-info.json" "/build/build-info.json"
  "/info" "/actuator/info" "/api/info"
  "/version" "/api/version" "/_version"
  "/health" "/status" "/ping"
  "/robots.txt" "/security.txt" "/.well-known/security.txt"
  "/sitemap.xml" "/manifest.json" "/browserconfig.xml"
  "/crossdomain.xml" "/clientaccesspolicy.xml"
  "/phpinfo.php" "/info.php" "/test.php"
  "/server-status" "/server-info" "/.htaccess"
  "/web.config" "/applicationHost.config"
  "/WEB-INF/web.xml" "/META-INF/MANIFEST.MF"
  "/package.json" "/composer.json" "/Gemfile"
  "/Dockerfile" "/docker-compose.yml" "/.dockerenv"
)

for PATH in "${DEBUG_PATHS[@]}"; do
  STATUS=$(curl --max-time 30 --connect-timeout 10 -s -o /tmp/debug_test -w "%{http_code}" "https://$TARGET$PATH")
  if [ "$STATUS" = "200" ]; then
    echo "[+] Found: https://$TARGET$PATH ($STATUS, $(wc -c < /tmp/debug_test) bytes)"
    head -3 /tmp/debug_test
    echo "---"
  fi
done

---

Phase 6 — .DS_Store File Listing

# .DS_Store files on macOS-deployed web servers reveal directory structure
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/.DS_Store" | xxd | head -10

# Parse .DS_Store to extract filenames
pip3 install ds_store
python3 -c "
from ds_store import DSStore
with DSStore.open('/tmp/ds_store_test', 'r') as d:
    for entry in d:
        print(entry.filename)
"

# Recursive .DS_Store enumeration
# Tool: https://github.com/lijiejie/ds_store_exp
python3 ds_store_exp.py "https://$TARGET/"

---

Phase 7 — webpack Chunk Analysis

⚠ BusyBox/Alpine: Skip grep -Eo below — use Python3 re instead (see Pitfalls section).

# Download and analyze webpack chunks for hardcoded values
# Find chunk files
curl --max-time 30 --connect-timeout 10 -s https://$TARGET/ | grep -Eo '"[^"]*\.chunk\.js"' | tr -d '"' | while read chunk; do
  echo "Analyzing: $chunk"
  curl --max-time 30 --connect-timeout 10 -s "https://$TARGET$chunk" | \
    grep -oE '"(api_key|apiKey|secret|password|token|key)"\s*:\s*"[^"]+"' | head -5
done

# Also grep for internal hostnames
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/static/js/main.*.js" | \
  grep -oE '"(https?://[^"]*internal[^"]*|http://[^"]*localhost[^"]*)"' | sort -u

# Check for Base64-encoded secrets
curl --max-time 30 --connect-timeout 10 -s "https://$TARGET/static/js/m

… (full content is in the download package)