# Recon Sector Expansion

> Multi-sector batch domain expansion — identify untested/under-tested sectors, generate candidate company domains (national chains, franchises, regionals), filter against existing test coverage, probe alive domains, and run the full testing pipeline across 20+ new targets in a single session. Complements per-sector recon-* skills by telling you WHICH sectors to expand into next.

- Skill: `uphiago/recon-sector-expansion` (Agent Skill)
- Install (CLI): `npx skillmds@latest add uphiago/recon-sector-expansion`
- Raw SKILL.md: https://api.skillmd.com/api/skills/uphiago/recon-sector-expansion/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: DevOps & Infra
- License: MIT
- Author: uphiago (https://skillmd.com/u/uphiago)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/uphiago/recon-sector-expansion

---


# RECON-SECTOR-EXPANSION — Batch Discovery Across Untapped Sectors

## When to Use

Use within authorized engagements to **expand coverage into fresh sectors** — not dig deeper into a single known target, but find and test 20+ new company domains across 5-10 different sectors. Target list must be from authorized scope. Batch expansion is for scoped programs, not indiscriminate scraping.

**Signals:**
- "Discover 20 more domains in non-regulated sectors"
- "We need to expand coverage; what haven't we tested?"
- "Find fresh targets outside the usual sectors"

## The Sector Expansion Workflow

### Phase 1 — Coverage Audit

Before discovering new targets, know what's already been tested:

```bash
# 1. Check existing target list
ALL_TARGETS="${OUTPUT_DIR:-./output}/sector-expansion/all_targets.txt"
ALL_MASSIVE="${OUTPUT_DIR:-./output}/sector-expansion/all_massive.txt"

# Extract all domains from both files
grep -ohE '[a-zA-Z0-9][a-zA-Z0-9.-]*\.[a-z]{2,}' "$ALL_TARGETS" "$ALL_MASSIVE" | sort -u > /tmp/targets_deduped.txt
echo "Already tested: $(wc -l < /tmp/targets_deduped.txt) domains"

# 2. Check what findings files exist
ls "${OUTPUT_DIR:-./output}"/sector-expansion/*_findings.md 2>/dev/null | wc -l

# 3. Identify which sectors have been covered by inspecting findings files
# Check for sector-specific keywords
for sector in "dentist" "dental" "gym" "fitness" "baker" "auto_body" "carpet" "laundry" "daycare" "pest" "tree" "pet"; do
  count=$(grep -l "$sector" "${OUTPUT_DIR:-./output}"/sector-expansion/*_findings*.md 2>/dev/null | wc -l)
  echo "Sector '$sector': $count findings files"
done
```

### Phase 2a — Source 1: crt.sh Certificate Transparency (Preferred for Local Business Sectors)

For **local service sectors** (roofing, landscaping, plumbing, pool services, HVAC) where no national chains exist, **crt.sh is the primary discovery source**. These businesses often have descriptive domain names like `[name][SECTOR_EXAMPLE]` or `[city][SECTOR_EXAMPLE]`.

#### crt.sh Query Pattern

Use simple sector keywords with the HTML output mode (JSON API returns 502/503 on broad queries):

```bash
QUERY="roofing"
curl -s --max-time 40 --connect-timeout 10 \
  "https://crt.sh/?q=${QUERY}&excluded=expired&dedup=Y" \
  -H 'User-Agent: Mozilla/5.0' 2>/dev/null | \
  grep -oE '>[A-Za-z0-9][A-Za-z0-9.-]*\.com<' | \
  sed 's/^>//;s/<$//' | \
  sort -u >> /tmp/all_crt_domains.txt
```

**Parameters explained:**
- `&excluded=expired` — only current certificates
- `&dedup=Y` — deduplicate certificates
- `-oE` regex — BusyBox-compatible (no `-P` flag available)
- No `&output=json` — JSON API is unreliable for broad queries

#### Sector Keyword Catalog

Query ALL these sectors to gather candidates:

```bash
SECTORS="roofing landscaping pestcontrol dentist dentist fitness \
cleaningservice movingcompany photography vetclinic realtor hvac \
treeservice lawncare plumbing poolcleaning windowcleaning petsalon \
barbershop daycare carpetcleaning handyman lawfirm concrete \
autorepair petgrooming autobody remodeling"
for sector in $SECTORS; do
  curl -s --max-time 40 --connect-timeout 10 "https://crt.sh/?q=${sector}&excluded=expired&dedup=Y" \
    -H 'User-Agent: Mozilla/5.0' 2>/dev/null | \
    grep -oE '>[A-Za-z0-9][A-Za-z0-9.-]*\.com<' | \
    sed 's/^>//;s/<$//' >> /tmp/all_crt_domains.txt
  sleep 2  # avoid rate limiting
done
```

#### Filtering Noise from crt.sh Results

crt.sh returns many subdomains and infrastructure hosts. Strip these patterns:

```python
import re

# Common noise patterns from crt.sh
skip_patterns = [
    '^autodiscover\\.', '^vpn\\.', '^api\\.', '^mail\\.', '^remote\\.',
    '^webmail\\.', '^crm\\.', '^ftp\\.', '^test\\.', '^dev\\.',
    '^exchange', '^hostmaster', '^owa\\.', '^smtp\\.',
    # Generic placeholder domains
    'roofingcompany\\.com$', 'landscapingcompany\\.com$', 'vetclinic\\.com$',
]
```

Then associate domains with sectors by matching their name:

```python
SECTOR_KEYWORDS = {
    'roofing': ['roofing', 'roof', 'roofer'],
    'landscaping': ['landscaping', 'landscape', 'lawn'],
    'hvac': ['hvac', 'heating', 'cooling', 'air'],
    'dental': ['dentist', 'dental'],
    'pest-control': ['pest', 'mosquito'],
    'daycare': ['daycare'],
    'legal': ['lawfirm', 'lawfirm'],
    'fitness': ['gym', 'fitness'],
    'auto-repair': ['autorepair', 'auto', 'collision'],
    'cleaning': ['cleaning', 'maid'],
    'veterinary': ['vet', 'pet'],
    'pool-services': ['pool', 'spa'],
}
```

#### Noise Subdomain Filtering

When using grep on crt.sh HTML output, you'll get entries from large hosting providers. Exclude:
- `autodiscover.*`, `vpn.*`, `api.*`, `mail.*`, `remote.*` — infrastructure
- `.*\.hvacrightnow\.com`, `.*\.hvacbrain\.com` — SaaS platforms (not actual targets)
- `.*\.theroofingprofessor\.com`, `.*\.bakerroofing\.com` — large org subdomains
- `.*\.singaporepools\.com`, `.*\.devsingaporepools\.com` — non-US

Piping through `grep -v` with exclusion patterns before dedup saves time.

### Phase 2b — Source 2: Google / Manual (Preferred for National Chains)

For sectors dominated by **national/regional chains** (dental, gyms, bakeries, auto body), use Google searches because chain domain names rarely contain sector keywords:

| Sector | How to Find Candidates | Example Chains |
|--------|----------------------|----------------|
| Dental chains | Google "top dental chains USA" | Aspen Dental, Gentle Dental, Coast Dental, DentalWorks, Heartland Dental, Pacific Dental |
| Gym/fitness | Google "largest fitness chains USA" | F45, Barry's, CrossFit, Gold's Gym, 24 Hour Fitness, LA Fitness, OrangeTheory |
| Bakery chains | Google "largest bakery chains USA" | Cinnabon, Crumbl, Insomnia Cookies, Sprinkles, Nothing Bundt Cakes |
| Auto body/collision | Google "auto body repair chains USA" | ABRA, Caliber, Gerber, Service King, Fix Auto, Sterling, Crash Champions |
| Carpet cleaning | Google "carpet cleaning companies USA" | Chem-Dry, ServPro, Stanley Steemer, Rainbow International, Heaven's Best |
| Laundry services | Google "laundry delivery service USA" | Poplin, Rinse, Washlava, LaundryHeap |
| Daycare/childcare | Google "largest daycare chains USA" | Bright Horizons, KinderCare, Goddard, Primrose, Children of America |
| Pet grooming | Google "pet grooming chains USA" | Petco, PetSmart, Camp Bow Wow, Dogtopia |
| Pest control | Google "pest control companies USA" | Terminix, Orkin, Ehrlich, Bulwark, Arrow |
| Tree services | Google "tree service companies USA" | Davey, SavATree, Arbor Care, Bartlett |

### Phase 3 — Batch Alive-Check (Curl Probe)

Once you have 50-60 candidate domains, filter against already-tested domains, then quick-check HTTP:

```bash
# Filter against known targets
grep -v -f /tmp/targets_deduped.txt /tmp/candidates.txt | sort -u > /tmp/fresh_candidates.txt

# Quick alive check with curl (serial, ~2.5 min for 60 targets)
echo "=== Checking all candidates with curl ==="
for domain in $(cat /tmp/fresh_candidates.txt); do
  code=$(curl -sk -o /dev/null -w '%{http_code}' --connect-timeout 5 --max-time 8 "https://${domain}" 2>/dev/null)
  echo "$domain => $code"
done > /tmp/curl_alive.txt

# Extract alive domains (anything not 000/timeout)
grep -v "=> 000" /tmp/curl_alive.txt | grep -v "^$" | cut -d' ' -f1 > /tmp/alive_domains.txt
echo "Alive: $(wc -l < /tmp/alive_domains.txt) / $(wc -l < /tmp/fresh_candidates.txt) candidates"
```

### Phase 4 — Full Testing Pipeline

Then run the full 6-step pipeline on alive domains. The most efficient approach at scale (20+ targets) is a Python batch script:

```python
#!/usr/bin/env python3
"""Batch test targets: httpx → WP REST → CORS → XMLRPC → ports"""
import subprocess, json, sys, os, re, time

OUTPUT_DIR = os.environ.get("OUTPUT_DIR", "./output") + "/sector-expansion"

def run(cmd, timeout=15):
    try:
        r = subprocess.run(cmd, shell=True, capture_output=True, text=True, timeout=timeout)
        return r.stdout + r.stderr
    except subprocess.TimeoutExpired:
        return f"TIMEOUT ({timeout}s)"
    except Exception as ex:
        return f"ERROR: {ex}"

def test_domain(domain, sector):
    findings = {"domain": domain, "sector": sector, "wp": False, "wp_users": 0,
                "cors_reflected": False, "xmlrpc_open": False}
    
    # STEP 1: httpx probe
    r = run(f"httpx -sc -title -tech-detect -server -no-color -u https://{domain} -timeout 10")
    findings["http"] = r.strip()
    
    # STEP 2: WordPress REST API check (3 paths)
    for path in ["/wp-json/wp/v2/users", "/wp-json/", "/?rest_route=/wp/v2/users"]:
        r = run(f'curl -sk -o /dev/null -w "%{{http_code}}" --max-time 10 --connect-timeout 10 "https://{domain}{path}"')
        if r in ["200"]:
            findings["wp_rest_status"] = f"{path} => HTTP {r}"
            findings["wp"] = True
            # Enumerate users
            user_resp = run(f'curl -sk --max-time 10 --connect-timeout 10 "https://{domain}{path}"', timeout=12)
            try:
                users = json.loads(user_resp)
                if isinstance(users, list):
                    findings["wp_users"] = len(users)
                    findings["wp_users_list"] = [u.get("name","") for u in users]
            except:
                pass
            break
    
    # Fallback: check page source for WP markers
    if not findings["wp"]:
        r = run(f'curl -sk --max-time 10 --connect-timeout 10 "https://{domain}"', timeout=12)
        if "/wp-content/" in r or "/wp-includes/" in r:
            findings["wp"] = True
    
    # STEP 3: CORS test
    target_url = f"https://{domain}/wp-json/wp/v2/users" if findings["wp"] else f"https://{domain}/"
    r = run(f'curl -sk -H "Origin: https://evil.com" -D- --max-time 10 --connect-timeout 10 "{target_url}" | grep -i access-control', timeout=12)
    if "Access-Control-Allow-Origin" in r:
        findings["cors_reflected"] = True
        findings["cors_credentialed"] = "Access-Control-Allow-Credentials" in r
    
    # STEP 4: XMLRPC check
    r = run(f'curl -sk -o /dev/null -w "%{{http_code}}" --max-time 10 --connect-timeout 10 -X POST "https://{domain}/xmlrpc.php"', timeout=12)
    findings["xmlrpc_open"] = (r.strip() == "200")
    
    # STEP 5: Port scan (top 20)
    r = run(f'nmap --top-ports 20 -T4 --open -n {domain}', timeout=120)
    ports = [line.split('/')[0] for line in r.split('\n') if re.search(r'^\d+/tcp\s+open', line)]
    findings["ports"] = ports
    
    # Severity calculation
    score = sum([findings["wp"], bool(findings["wp_users"] > 0), findings["cors_reflected"], findings["xmlrpc_open"]])
    findings["vuln"] = "HIGH" if score >= 3 else ("MEDIUM" if score >= 2 else ("LOW" if score >= 1 else "NONE"))
    
    return findings

# Usage
domains = {"[TARGET_1]": "dental", "[TARGET_2]": "gym_fitness", ...}
for domain, sector in domains.items():
    f = test_domain(domain, sector)
    # Write findings.md
    content = f"""## {domain}
| Field | Value |
|-------|-------|
| HTTP | {f['http'][:200]} |
| WordPress | {'Yes' if f['wp'] else 'No'}, users: {f['wp_users']} |
| CORS | {'Reflected' + (' WITH CREDENTIALS' if f.get('cors_credentialed') else '') if f['cors_reflected'] else 'Not reflected'} |
| XMLRPC | {'Open' if f['xmlrpc_open'] else 'Closed'} |
| Ports | {', '.join(f['ports']) if f['ports'] else 'none found'} |
| Sector | {sector} |
| Vuln | {f['vuln']} |
"""
    with open(f"{OUTPUT_DIR}/{domain}_findings.md", 'w') as out:
        out.write(content)
```

### Phase 5 — Results Analysis

Review findings for these high-signal patterns:

| Pattern | How to Spot | Severity |
|---------|------------|----------|
| **Credentialled CORS** | `Access-Control-Allow-Origin: http://evil.com` + `Access-Control-Allow-Credentials: true` on `/wp-json/wp/v2/users` | HIGH |
| **WordPress users exposed** | REST API at `/wp-json/wp/v2/users` returns array of user objects with names, slugs, avatars | MEDIUM |
| **Wildcard CORS** | `Access-Control-Allow-Origin: *` (no credentials) | MEDIUM |
| **XMLRPC open** | `/xmlrpc.php` returns HTTP 200 (may be blocked at method-list level by WAF) | LOW-MEDIUM |
| **Open ports on non-standard services** | 21 (FTP), 3306 (MySQL), 3389 (RDP), 5900 (VNC), 6379 (Redis) | VARIES |
| **PHPInfo exposed** | `/info.php`, `/test.php`, etc reveal 400+ config entries | LOW |

## Sector-Specific Chains Domain List

Curated list of US national/regional chain domains (verified alive as of 2026-06):

### Dental
```
aspendental.com  gentledental.com  dentalworks.com  coastdental.com
brightnow.com    sagedental.com    western-dental.com  castledental.com
heartlanddental.com  pacificdental.com  dentalcarealliance.com
```

### Gym / Fitness
```
[FITNESS_CHAIN]  barrys.com  crossfit.com  goldsgym.com
24hourfitness.com  lafitness.com  orangetheory.com  planetfitness.com
anytimefitness.com  snapfitness.com  crunch.com
```

### Bakery
```
cinnabon.com  crumbl.com  insomniacookies.com  sprinkles.com
bakery.example.com  restaurant.example.com  donut.example.com
```

### Auto Body / Collision Repair
```
abracollision.com  serviceking.com  sterlingautobody.com  crashchampions.com
fixauto.com  true2form.com  auto-body-shop.com
calibercollision.com  carstar.com  gerbercollision.com  maaco.com
```

### Carpet Cleaning
```
chemdry.com  servpro.com  rainbowintl.com  heavenlycarpet.com
stanleysteemer.com  zerorez.com  coit.com
```

### Laundry
```
poplin.com  rinse.com  washlava.com  laundryheap.com
speedqueen.com  spincyclelaundry.com
```

### Daycare
```
brighthorizons.com  childrenofamerica.com  kindercare.com  goddardschool.com
primroseschools.com  montessori.com  lajollamontessori.com  tutortime.com
```

### Pest Control
```
terminix.com  orkin.com  echols.com  bulwarkpest.com
arrowpest-control.example.com  dodsonbros.com  massey-services.com
```

### Tree Services
```
treecare.com  arborcare.com  davey.com  savatree.com
bartlett.com  allstatetree.com  firstchoicetree.com
```

### Roofing (Local/Regional — crt.sh Discovered)
```
aastro[SECTOR_EXAMPLE]  abcarnes[SECTOR_EXAMPLE]  americaschoiceroofers.com  arvada[SECTOR_EXAMPLE]
bacon[SECTOR_EXAMPLE]  baker[SECTOR_EXAMPLE]  bricor[SECTOR_EXAMPLE]  capitol[SECTOR_EXAMPLE]
charlottepro[SECTOR_EXAMPLE]  coloradopro[SECTOR_EXAMPLE]  eh[SECTOR_EXAMPLE]  errdaddy[SECTOR_EXAMPLE]
fifthwall[SECTOR_EXAMPLE]  freeman[SECTOR_EXAMPLE]  ghatley.com  hambro[SECTOR_EXAMPLE]
hollis[SECTOR_EXAMPLE]  integrityrc.com  kbfamily[SECTOR_EXAMPLE]  mcas[SECTOR_EXAMPLE]
na[SECTOR_EXAMPLE]  pabco[SECTOR_EXAMPLE]  roofon.com  roofwithfoster.com
sandiegocounty[SECTOR_EXAMPLE]  springfield[SECTOR_EXAMPLE]  tomtheroofer.com
universityroof.com  vanguardroofingltd.com  wallace[SECTOR_EXAMPLE]
```

### Landscaping (Local/Regional — crt.sh Discovered)
```
delliquadrilandscape.com  dundeedig.com  guardyouryardpa.com
landscapingsi.com  miles[SECTOR_EXAMPLE]  moss[SECTOR_EXAMPLE]
mountainlandscapingkc.com  sarasota[SECTOR_EXAMPLE]  trinas[SECTOR_EXAMPLE]
moss[SECTOR_EXAMPLE]  eo[SECTOR_EXAMPLE]  brucewilson[SECTOR_EXAMPLE]
```

### HVAC (Local/Regional — crt.sh Discovered)
```
airzonahvac.com  bigfishhvac.com  dormarhvac.com  specializedhvac.com
```

### General Contractors & Other (crt.sh Discovered)
```
allysonsflowers.com  [INSURANCE_CO]  canopyroofers.com
gelinc.com  rvroofrepairflorida.com  spartanroofingbc.com
```

## Pitfalls

1. **Don't rely on a single key file for "tested" domains.** `all_targets.txt` and `all_massive.txt` may differ. Merge both and deduplicate with `sort -u`.

2. **CloudFlare blocks WP REST API for some sites.** If you get HTTP 403 on `/wp-json/wp/v2/users`, try `/?rest_route=/wp/v2/users` or check page source for `/wp-content/` markers.

3. **XMLRPC may return 200 but block system.listMethods.** CloudFlare and other WAFs block the method-listing XML body but leave the endpoint open for `system.multicall`. Test separately.

4. **Some 301/302 sites may still have CORS.** Redirect responses can carry CORS headers (brighthorizons.com had wildcard CORS on its 301 response). Test the redirect target URL if the landing page differs.

5. **BusyBox grep limitation.** Minimal environments may provide BusyBox,
   which lacks `grep -P`. Use `grep -oE` with extended patterns. BusyBox `find`
   also lacks `-printf`; use `-exec echo {} \;` or shell loops instead.

6. **crt.sh rate limiting.** Returns HTTP 502/503 when hammered. Spread queries **3 seconds apart** and if you get repeated errors, wait 15-30s. The JSON API (`&output=json`) is especially unreliable for broad queries — use HTML output mode (`&excluded=expired&dedup=Y`) instead.

7. **Port scan timing.** `nmap --top-ports 20 -T4` takes ~3-5s per target. Parallelize across 5-7 targets in background.

8. **CORS on non-WordPress sites.** Generic static sites on CloudFront or S3 may also reflect CORS. Always test on both `/` and any known API endpoint.

9. **Python JSON parsing edge case.** The WP REST API user endpoint may return an object instead of a list for protected endpoints (HTTP 401 vs 200 response codes). Always check `isinstance(users, list)`.

## Verification
1. **Sector domain generation** — confirm sector keywords produce candidate domains:
   ```bash
   echo 'roofing landscaping pestcontrol' | tr ' ' '
' | wc -l
   ```
2. **crt.sh accessibility** — confirm crt.sh CDX endpoint reachable:
   ```bash
   curl -s --max-time 10 --connect-timeout 10 -o /dev/null -w '%{http_code}' 'https://crt.sh/?q=test&excluded=expired&dedup=Y'
   ```
All tests verify sector expansion readiness.

---

## Related Skills

- `web2-recon` — The per-target technical testing pipeline (httpx, WP enum, CORS, XMLRPC, port scan, JS analysis)
- `recon-sector` — Unified parameterized sector recon with 25 sectors in `sectors.yaml`