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Full WSTG-aligned web application pentest — 12-phase methodology from information gathering through reporting, with concrete commands, expected outputs, pitfalls, and verification per phase.
Attack SAML SSO via XSW, signature strip, metadata extract.
Use when two or more verified findings may combine into a higher-impact authorized attack path.
Based on SOC occupation classification
Showing SKILL.md
| name | subdomain-enumeration |
| description | Map subdomains via crt.sh and subfinder at recon kickoff. |
| version | 1.1.0 |
| revision_date | "2026-07-25T00:00:00.000Z" |
| license | MIT |
| platforms | ["linux"] |
| compatibility | Requires curl, subfinder, httpx, dnsx, dig, jq |
| tags | ["recon","subdomain","DNS","crt.sh","asset-discovery"] |
| category | recon |
| related_skills | ["wp-mass-recon","staging-subdomain-hunt","deep-invade","recon-playbook"] |
Comprehensive subdomain discovery using certificate transparency logs (crt.sh), DNS brute force, and passive sources. The first step in any recon pipeline — you can't attack what you don't know exists. Subdomain enumeration consistently reveals staging environments, internal admin panels, API gateways, and forgotten WordPress installs that are softer targets than the production site.
skill_view(name='wp-mass-recon') — enumerate subdomains for each WordPress target.curl, httpx, dig, jq, dnsx, and subfinder.DOMAIN="example.com"
# Passive: crt.sh
curl --max-time 30 --connect-timeout 10 -sk "https://crt.sh/?q=%25.$DOMAIN&output=json" | jq -r '.[].name_value' | sed 's/\*\.//g' | sort -u > crtsh.txt
# Passive: subfinder
subfinder -d "$DOMAIN" -silent > subfinder.txt
# Merge and deduplicate
cat crtsh.txt subfinder.txt | sort -u > all_subs.txt
# Probe live hosts
httpx -silent -l all_subs.txt -threads 50 -status-code -tech-detect -title -o alive.txt
| Source | Method | Coverage | Speed |
|---|---|---|---|
| crt.sh | Certificate transparency | Excellent (most certs) | Fast (1-5s) |
| subfinder | Passive APIs (VirusTotal, Shodan, DNSdumpster, etc.) | Very good | Fast (30-60s) |
| dnsx | Bulk DNS A/AAAA/CNAME resolution (100x faster than dig) | Good (uncovers non-HTTP) |
| Fast (10-30s) |
| httpx probe | Live HTTP/HTTPS check | Best for web attack surface | Fast (30-60s) |
| Google dork | site:example.com | Supplemental | Manual |
DOMAIN="$1"
OUTDIR="$OUTDIR/subdomains/$DOMAIN"
mkdir -p "$OUTDIR"
echo "[*] Passive enumeration for $DOMAIN..."
# crt.sh — certificate transparency logs
echo "[*] crt.sh query..."
curl -sk --max-time 30 --connect-timeout 10 "https://crt.sh/?q=%25.$DOMAIN&output=json" 2>/dev/null | \
jq -r '.[].name_value' 2>/dev/null | \
sed 's/\*\.//g' | \
sed 's/^www\.//' | \
sort -u > "$OUTDIR/crtsh.txt"
crt_count=$(wc -l < "$OUTDIR/crtsh.txt")
echo " crt.sh: $crt_count entries"
# Also query with %25. (wildcard)
curl -sk --max-time 30 --connect-timeout 10 "https://crt.sh/?q=%25.%25.$DOMAIN&output=json" 2>/dev/null | \
jq -r '.[].name_value' 2>/dev/null | \
sed 's/\*\.//g' | \
sort -u > "$OUTDIR/crtsh_wildcard.txt"
# subfinder — passive API aggregation
echo "[*] subfinder..."
subfinder -d "$DOMAIN" -silent -timeout 30 2>/dev/null | sort -u > "$OUTDIR/subfinder.txt"
subf_count=$(wc -l < "$OUTDIR/subfinder.txt")
echo " subfinder: $subf_count entries"
# Merge all passive sources
cat "$OUTDIR"/crtsh.txt "$OUTDIR"/crtsh_wildcard.txt "$OUTDIR"/subfinder.txt 2>/dev/null | \
sed 's/^www\.//' | \
grep -E '^[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$' | \
sort -u > "$OUTDIR/all_passive.txt"
total=$(wc -l < "$OUTDIR/all_passive.txt")
echo ""
echo "[+] Total unique subdomains (passive): $total"
DOMAIN="$1"
OUTDIR="$OUTDIR/subdomains/$DOMAIN"
echo "[*] Resolving subdomains..."
# Batch resolve with dnsx (100x faster than dig loop)
dnsx -silent -l "$OUTDIR/all_passive.txt" -a -resp-only -o "$OUTDIR/resolved_raw.txt" 2>/dev/null
# Format output: subdomain => IP
while read -r line; do
sub=$(echo "$line" | cut -d' ' -f1)
ip=$(echo "$line" | cut -d' ' -f2)
echo "$sub => $ip"
done < "$OUTDIR/resolved_raw.txt" > "$OUTDIR/resolved.txt"
resolved=$(wc -l < "$OUTDIR/resolved.txt")
echo "[+] $resolved subdomains resolved to IPs"
# Count unique IPs
unique_ips=$(awk '{print $3}' "$OUTDIR/resolved.txt" | sort -u | wc -l)
echo "[+] $unique_ips unique IPs"
# Identify shared hosting (many subdomains → same IP)
echo ""
echo "[*] Shared hosting clusters:"
awk '{print $3}' "$OUTDIR/resolved.txt" | sort | uniq -c | sort -rn | head -10 | while read -r count ip; do
[[ "$count" -gt 1 ]] && echo " $ip: $count subdomains"
done
DOMAIN="$1"
OUTDIR="$OUTDIR/subdomains/$DOMAIN"
echo "[*] Probing live hosts..."
# httpx with tech detection
httpx -silent -l "$OUTDIR/all_passive.txt" -threads 50 \
-status-code -tech-detect -title -location \
-o "$OUTDIR/alive.txt" 2>/dev/null
alive=$(wc -l < "$OUTDIR/alive.txt")
echo "[+] $alive live hosts"
# Categorize by status code
echo ""
echo "[*] By HTTP status:"
echo " 200: $(grep -c '\[200\]' "$OUTDIR/alive.txt")"
echo " 301/302: $(grep -cE '\[301\]|\[302\]' "$OUTDIR/alive.txt")"
echo " 403: $(grep -c '\[403\]' "$OUTDIR/alive.txt")"
echo " 404: $(grep -c '\[404\]' "$OUTDIR/alive.txt")"
# Categorize by technology
echo ""
echo "[*] By technology:"
grep -Eo '\[[a-z-]+\]' "$OUTDIR/alive.txt" | tr -d '[]' | sort | uniq -c | sort -rn | head -15
# WordPress subdomains
echo ""
echo "[*] WordPress subdomains:"
grep -i 'wordpress' "$OUTDIR/alive.txt" | awk '{print $1}' | head -10
# Non-HTTP services (from DNS resolution)
echo ""
echo "[*] Interesting non-standard ports from DNS (MX, NS, etc.):"
dig +short "$DOMAIN" MX 2>/dev/null | head -5
dig +short "$DOMAIN" NS 2>/dev/null | head -5
dig +short "$DOMAIN" TXT 2>/dev/null | grep -i 'spf\|v=spf' | head -3
DOMAIN="$1"
OUTDIR="$OUTDIR/subdomains/$DOMAIN"
echo "[*] Categorizing subdomains..."
# Staging/Dev
echo ""
echo "=== STAGING / DEV ==="
grep -iE 'staging|stage|dev\.|development|test|uat|beta|sandbox|preview|qa' "$OUTDIR/all_passive.txt"
# Admin/Internal
echo ""
echo "=== ADMIN / INTERNAL ==="
grep -iE 'admin|portal|internal|dashboard|manage|cp\.|control|panel|cpanel|webmail|mail\.' "$OUTDIR/all_passive.txt"
# API
echo ""
echo "=== API ==="
grep -iE 'api|rest|graphql|ws\.|websocket' "$OUTDIR/all_passive.txt"
# Infrastructure
echo ""
echo "=== CDN / STATIC ==="
grep -iE 'cdn|static|assets|media|img|images|files|download|origin|proxy' "$OUTDIR/all_passive.txt"
# Email
echo ""
echo "=== EMAIL ==="
grep -iE 'mail\.|smtp|imap|pop|email|webmail|autodiscover' "$OUTDIR/all_passive.txt"
# Cloud
echo ""
echo "=== CLOUD ==="
grep -iE 'aws|azure|gcp|cloud|s3|bucket|firebase' "$OUTDIR/all_passive.txt"
# Legacy
echo ""
echo "=== LEGACY / OLD ==="
grep -iE 'old|old\.|v1|v2|legacy|archive|backup|bak' "$OUTDIR/all_passive.txt"
DOMAIN="$1"
OUTDIR="$OUTDIR/subdomains/$DOMAIN"
echo "[*] Checking for subdomain takeover opportunities..."
# Check for dangling CNAMEs (subdomains pointing to non-existent services)
# For bulk CNAME check: dnsx -silent -l all_passive.txt -cname -resp-only
while read -r sub; do
cname=$(dig +short "$sub" CNAME 2>/dev/null)
if [[ -n "$cname" ]]; then
# Check if the CNAME target resolves
cname_ip=$(dig +short "$cname" A 2>/dev/null)
if [[ -z "$cname_ip" ]]; then
echo "[TAKEOVER?] $sub => $cname (NOT RESOLVING)"
# Identify provider from CNAME
if echo "$cname" | grep -qi 'amazonaws.com'; then
echo " Provider: AWS (S3/CloudFront) — check if bucket/domain is claimable"
elif echo "$cname" | grep -qi 'azure'; then
echo " Provider: Azure — check if resource is claimable"
elif echo "$cname" | grep -qi 'github.io'; then
echo " Provider: GitHub Pages — check if repo name is available"
elif echo "$cname" | grep -qi 'herokuapp.com'; then
echo " Provider: Heroku — check if app name is available"
elif echo "$cname" | grep -qi 'vercel-dns.com'; then
echo " Provider: Vercel — check if project is claimable"
elif echo "$cname" | grep -qi 'zendesk.com'; then
echo " Provider: Zendesk — check if help desk is claimable"
fi
fi
fi
sleep 0.5
done < "$OUTDIR/all_passive.txt"
~/.config/subfinder/provider-config.yaml. Without them, results are limited.*.example.com resolves to the same IP, all subdomains will appear "live" in httpx. Check for wildcard by resolving a random string: dig RANDOMSTRING.example.com.Generate smart mutations from already-discovered subdomains to find hidden services:
# gotator — generates permutations
gotator -sub all_subs.txt -perm permutations.txt -depth 1 -numbers 3 -md | sort -u > subs_permuted.txt
# Resolve permutations
puredns resolve subs_permuted.txt -r resolvers.txt -o subs_permuted_alive.txt
# Common permutation patterns for the wordlist
# %s-dev, dev-%s, %s-staging, staging-%s, %s-prod, %s-internal
# %s-admin, admin-%s, %s-api, api-%s, %s-test, test-%s
# %s-stg, stg-%s, %s-uat, uat-%s, %s-www, www-%s
A company that owns target.com often neglects target.io, target.net, target.xyz:
# tldbrute — discovers registered TLD variants
tldbrute -d target.com
# Manual IANA TLD list approach
wget -q https://data.iana.org/TLD/tlds-alpha-by-domain.txt
ROOT=$(echo "target.com" | cut -d. -f1)
cat tlds-alpha-by-domain.txt | tr '[:upper:]' '[:lower:]' \
| while read tld; do echo "$ROOT.$tld"; sleep 0.2; done \
| httpx -silent -mc 200 > tlds_alive.txt
# Expand existing subdomains across TLDs
cat all_subs.txt | while read sub; do
cat tlds-alpha-by-domain.txt | tr '[:upper:]' '[:lower:]' \
| sed "s/^/$sub./"
done | dnsx -silent > subs_tld_expanded.txt
Catch new subdomains the moment they're issued:
# gungnir — real-time certificate transparency monitoring
gungnir -d target.com
# certwatcher — alternative CT log monitor
certwatcher -d target.com --webhook https://hooks.slack.com/xxx