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subfinder is a subdomain discovery tool that returns valid subdomains for websites, using passive online sources. It has a simple, modular architecture and is optimized for speed. subfinder is built for
doing one thing only - passive subdomain enumeration, and it does that very well.
We have made it to comply with all the used passive source licenses and usage restrictions. The passive model guarantees speed and stealthiness that can be leveraged by both penetration testers and bug bounty hunters alike.
- Fast and powerful resolution and wildcard elimination modules
- Curated passive sources to maximize results
- Multiple output formats supported (JSON, file, stdout)
- Optimized for speed and lightweight on resources
- STDIN/OUT support enables easy integration into workflows
subfinder -hThis will display help for the tool. Here are all the switches it supports.
Usage:
./subfinder [flags]
Flags:
INPUT:
-d, -domain string[] domains to find subdomains for
-dL, -list string file containing list of domains for subdomain discovery
SOURCE:
-s, -sources string[] specific sources to use for discovery (-s crtsh,github). Use -ls to display all available sources.
-recursive use only sources that can handle subdomains recursively (e.g. subdomain.domain.tld vs domain.tld)
-all use all sources for enumeration (slow)
-es, -exclude-sources string[] sources to exclude from enumeration (-es alienvault,zoomeye)
FILTER:
-m, -match string[] subdomain or list of subdomain to match (file or comma separated)
-f, -filter string[] subdomain or list of subdomain to filter (file or comma separated)
RATE-LIMIT:
-rl, -rate-limit int maximum number of http requests to send per second
-t int number of concurrent goroutines for resolving (-active only) (default 10)
UPDATE:
-up, -update update subfinder to latest version
-duc, -disable-update-check disable automatic subfinder update check
OUTPUT:
-o, -output string file to write output to
-oJ, -json write output in JSONL(ines) format
-oD, -output-dir string directory to write output (-dL only)
-cs, -collect-sources include all sources in the output (-json only)
-oI, -ip include host IP in output (-active only)
CONFIGURATION:
-config string flag config file (default "$HOME/.config/subfinder/config.yaml")
-pc, -provider-config string provider config file (default "$HOME/.config/subfinder/provider-config.yaml")
-r string[] comma separated list of resolvers to use
-rL, -rlist string file containing list of resolvers to use
-nW, -active display active subdomains only
-proxy string http proxy to use with subfinder
-ei, -exclude-ip exclude IPs from the list of domains
DEBUG:
-silent show only subdomains in output
-version show version of subfinder
-v show verbose output
-nc, -no-color disable color in output
-ls, -list-sources list all available sources
OPTIMIZATION:
-timeout int seconds to wait before timing out (default 30)
-max-time int minutes to wait for enumeration results (default 10)subfinder requires go1.19 to install successfully. Run the following command to install the latest version:
go install -v github.com/projectdiscovery/subfinder/v2/cmd/subfinder@latestsubfinder can be used right after the installation, however the following services require configuring API keys to work:
BeVigil, BinaryEdge, BufferOver, C99, Censys, CertSpotter, Chaos, Chinaz, DnsDB, Fofa, FullHunt, GitHub, Intelx, PassiveTotal, quake, Robtex, SecurityTrails, Shodan, ThreatBook, VirusTotal, WhoisXML API, ZoomEye, ZoomEye API, dnsrepo, Hunter
You can also use the subfinder -ls command to display all the available sources.
These values are stored in the $HOME/.config/subfinder/provider-config.yaml file which will be created when you run the tool for the first time. The configuration file uses the YAML format. Multiple API keys
can be specified for each of these services from which one of them will be used for enumeration.
Composite keys for sources like, Censys, PassiveTotal, Fofa, Intellix and ZoomEye, need to be separated with a colon (:).
An example provider config file:
binaryedge:
- 0bf8919b-aab9-42e4-9574-d3b639324597
- ac244e2f-b635-4581-878a-33f4e79a2c13
censys:
- ac244e2f-b635-4581-878a-33f4e79a2c13:dd510d6e-1b6e-4655-83f6-f347b363def9
certspotter: []
passivetotal:
- sample-email@user.com:sample_password
securitytrails: []
shodan:
- AAAAClP1bJJSRMEYJazgwhJKrggRwKA
github:
- ghp_lkyJGU3jv1xmwk4SDXavrLDJ4dl2pSJMzj4X
- ghp_gkUuhkIYdQPj13ifH4KA3cXRn8JD2lqir2d4
zoomeye:
- zoomeye_username:zoomeye_passwordTo run the tool on a target, just use the following command.
subfinder -d hackerone.com
__ _____ __
_______ __/ /_ / __(_)___ ____/ /__ _____
/ ___/ / / / __ \/ /_/ / __ \/ __ / _ \/ ___/
(__ ) /_/ / /_/ / __/ / / / / /_/ / __/ /
/____/\__,_/_.___/_/ /_/_/ /_/\__,_/\___/_/ v2.4.9
projectdiscovery.io
Use with caution. You are responsible for your actions
Developers assume no liability and are not responsible for any misuse or damage.
By using subfinder, you also agree to the terms of the APIs used.
[INF] Enumerating subdomains for hackerone.com
www.hackerone.com
support.hackerone.com
links.hackerone.com
api.hackerone.com
o1.email.hackerone.com
go.hackerone.com
3d.hackerone.com
resources.hackerone.com
a.ns.hackerone.com
b.ns.hackerone.com
mta-sts.hackerone.com
docs.hackerone.com
mta-sts.forwarding.hackerone.com
gslink.hackerone.com
hackerone.com
info.hackerone.com
mta-sts.managed.hackerone.com
events.hackerone.com
[INF] Found 18 subdomains for hackerone.com in 3 seconds 672 millisecondsThe subdomains discovered can be piped to other tools too. For example, you can pipe the discovered subdomains to httpx which will then find
running HTTP servers on the host.
echo hackerone.com | subfinder -silent | httpx -silent
http://hackerone.com
http://www.hackerone.com
http://docs.hackerone.com
http://api.hackerone.com
https://docs.hackerone.com
http://mta-sts.managed.hackerone.com|
Pull the latest tagged subfinder docker image: docker pull projectdiscovery/subfinder:latestRunning docker run projectdiscovery/subfinder:latest -d hackerone.comRunning docker run -v $HOME/.config/subfinder:/root/.config/subfinder -t projectdiscovery/subfinder -d hackerone.com |
|
Usage example: package main
import (
"bytes"
"fmt"
"io"
"log"
"github.com/projectdiscovery/subfinder/v2/pkg/resolve"
"github.com/projectdiscovery/subfinder/v2/pkg/runner"
)
func main() {
runnerInstance, err := runner.NewRunner(&runner.Options{
Threads: 10, // Thread controls the number of threads to use for active enumerations
Timeout: 30, // Timeout is the seconds to wait for sources to respond
MaxEnumerationTime: 10, // MaxEnumerationTime is the maximum amount of time in mins to wait for enumeration
Resolvers: resolve.DefaultResolvers, // Use the default list of resolvers by marshaling it to the config
ResultCallback: func(s *resolve.HostEntry) { // Callback function to execute for available host
log.Println(s.Host, s.Source)
},
})
buf := bytes.Buffer{}
err = runnerInstance.EnumerateSingleDomain("projectdiscovery.io", []io.Writer{&buf})
if err != nil {
log.Fatal(err)
}
data, err := io.ReadAll(&buf)
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s", data)
} |
subfinder is made with 🖤 by the projectdiscovery team. Community contributions have made the project what it is. See
the THANKS.md file for more details.
Read the usage disclaimer at DISCLAIMER.md and contact us for any API removal.