Automated Enumeration
Subfinder
subfinder -d example.com -all -recursive -o subfinder.txt
Fast subdomain discovery using multiple data sources
Assetfinder
assetfinder --subs-only example.com > assetfinder.txt
Find domains and subdomains related to a given domain
Findomain
findomain -t example.com | tee findomain.txt
Cross-platform subdomain enumerator
Amass Passive
amass enum -passive -d example.com | cut -d']' -f 2 | awk '{print $1}' | sort -u > amass.txt
Passive subdomain enumeration using OSINT
Amass Active
amass enum -active -d example.com | cut -d']' -f 2 | awk '{print $1}' | sort -u > amass.txt
Active subdomain enumeration with DNS resolution
Public Sources
Certificate Transparency
curl -s https://crt.sh\?q\=\example.com\&output\=json | jq -r '.[].name_value' | grep -Po '(\w+\.\w+\.\w+)$' >crtsh.txt
Extract subdomains from Certificate Transparency logs
Wayback Machine
curl -s "http://web.archive.org/cdx/search/cdx?url=*.example.com/*&output=text&fl=original&collapse=urlkey" |sort| sed -e 's_https*://__' -e "s/\/.*//" -e 's/:.*//' -e 's/^www\.//' | sort -u > wayback.txt
Discover subdomains from archived pages
VirusTotal
curl -s "https://www.virustotal.com/vtapi/v2/domain/report?apikey=[api-key]&domain=example.com" | jq -r '.domain_siblings[]' > virustotal.txt
Get domain siblings from VirusTotal
GitHub Subdomains
github-subdomains -d example.com -t [github_token]
Find subdomains in GitHub repositories
Subdomain Processing
Merge & Deduplicate
cat *.txt | sort -u > final.txt
Combine all subdomain files and remove duplicates
Subdomain Permutation
subfinder -d example.com | alterx | dnsx
Generate subdomain permutations and resolve them
Alterx Enrichment
echo example.com | alterx -enrich | dnsx
Enrich domain with common patterns
Alterx with Wordlist
echo example.com | alterx -pp word=/usr/share/seclists/Discovery/DNS/subdomains-top1million-5000.txt | dnsx
Use wordlist for subdomain permutation
FFUF Subdomain Bruteforce
ffuf -u "https://FUZZ.example.com" -w wordlist.txt -mc 200,301,302
Brute force subdomains using FFUF