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.
npx skills add https://github.com/elementalsouls/Claude-BugHunter --skill hunt-source-leak
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 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 clone the 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# 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
> **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 .map URL 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.
>
> `bash
> # 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 to
> main.<hashB>.js — and the map was still published at main.<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 .map at 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
# 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$PATH"
# Extract all API paths from swagger
python3 -c "
import sys, json
try:
d = json.load(open('/tmp/swagger_test'))
paths = list(d.get('paths', {}).keys())
print(f'Endpoints: {len(paths)}')
print('\n'.join(sorted(paths)))
except: pass
" | head -50
fi
done
# Check if .git directory is accessible
curl -s "https://$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" $(git rev-list --all) 2>/dev/null | head -30
# trufflehog on git history
trufflehog git file:///tmp/dumped-repo/ 2>/dev/null | head -50
# Build artifacts and debug files
DEBUG_PATHS=(
"/build-info.json" "/build/build-info.json"
"/info" "/actuator/info" "/api/info"
"/version" "/api/version" "/_version"
"/health" "/status" "/ping"
"/robots.txt" "/security.txt" "/.well-known/security.txt"
"/sitemap.xml" "/manifest.json" "/browserconfig.xml"
"/crossdomain.xml" "/clientaccesspolicy.xml"
"/phpinfo.php" "/info.php" "/test.php"
"/server-status" "/server-info" "/.htaccess"
"/web.config" "/applicationHost.config"
"/WEB-INF/web.xml" "/META-INF/MANIFEST.MF"
"/package.json" "/composer.json" "/Gemfile"
"/Dockerfile" "/docker-compose.yml" "/.dockerenv"
)
for PATH in "${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, $(wc -c < /tmp/debug_test) bytes)"
head -3 /tmp/debug_test
echo "---"
fi
done
# .DS_Store files on macOS-deployed web servers reveal directory structure
curl -s "https://$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://$TARGET/"
# Download and analyze webpack chunks for hardcoded values
# Find chunk files
curl -s https://$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
| 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 |
# 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/
✅ 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:
Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).
Automatically creates user-facing changelogs from git commits by analyzing commit history, categorizing changes, and transforming technical commits into clear, customer-friendly release notes. Turns hours of manual changelog writing into minutes of automated generation.
Use when implementation is complete, all tests pass, and you need to decide how to integrate the work - guides completion of development work by presenting structured options for merge, PR, or cleanup
Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).
React Native and Expo best practices for building performant mobile apps. Use when building React Native components, optimizing list performance, implementing animations, or working with native modules. Triggers on tasks involving React Native, Expo, mobile performance, or native platform APIs.
React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance improvements.
Next.js best practices - file conventions, RSC boundaries, data patterns, async APIs, metadata, error handling, route handlers, image/font optimization, bundling
Use when starting feature work that needs isolation from current workspace or before executing implementation plans - creates isolated git worktrees with smart directory selection and safety verification
Take elementalsouls/hunt-source-leak from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.
The instructions reference pip, npm.
Without those the skill loads but fails at the first command.