The OWASP Amass tool suite obtains subdomain names by scraping data sources, recursive brute forcing, crawling web archives, permuting/altering names and reverse DNS sweeping. Additionally, Amass uses the IP addresses obtained during resolution to discover associated netblocks and ASNs. All the information is then used to build maps of the target networks.

A precompiled version is available for each release.

If you are on a distribution such as Kali Linux, and have never used snap previously, follow these steps to access snap packages:

$ sudo apt install snapd

$ sudo systemctl start snapd

Add the snap binaries to your PATH using a method similar to the following:

$ export PATH=$PATH:/snap/bin

If your operating environment supports Snap, you can click here to install, or perform the following from the command-line:

$ sudo snap install amass

If you would like snap to get you the latest unstable build of OWASP Amass, type the following command:

$ sudo snap install --edge amass

Periodically, execute the following command to update all your snap packages:

$ sudo snap refresh

1. Build the Docker image:

sudo docker build -t amass https://github.com/OWASP/Amass.git

2. Run the Docker image:

sudo docker run amass --passive -d example.com

If you would prefer to build your own binary from the latest version of the source code, make sure you have a correctly configured Go >= 1.10 environment. More information about how to achieve this can be found on the golang website. Then, take the following steps:

1. Download amass:

$ go get -u github.com/OWASP/Amass/...

2. If you wish to rebuild the binaries from the source code:

$ cd $GOPATH/src/github.com/OWASP/Amass

$ go install ./...

At this point, the binaries should be in $GOPATH/bin.

3. Several wordlists can be found in the following directory:

$ ls $GOPATH/src/github.com/OWASP/Amass/wordlists/

The most basic use of the tool, which includes reverse DNS lookups and name alterations:

$ amass -d example.com

The example below is a good place to start with amass:

$ amass -v -ip -brute -min-for-recursive 3 -d example.com
[Google] www.example.com
[VirusTotal] ns.example.com
...
13139 names discovered - archive: 171, cert: 2671, scrape: 6290, brute: 991, dns: 250, alt: 2766

Add some additional domains to the enumeration:

$ amass -d example1.com,example2.com -d example3.com

Switches available through the amass CLI:

Caution: If you use the amass.netdomains tool, it will attempt to reach out to every IP address within the identified infrastructure and obtain domains names from reverse DNS requests and TLS certificates. This is "loud" and can reveal your reconnaissance activities to the organization being investigated.

Lookup ASNs by searching the descriptions registered by organizations:

$ amass.netdomains -org Facebook
32934, US, ARIN, FACEBOOK - Facebook, Inc., US
54115, US, ARIN, FACEBOOK-CORP - Facebook Inc, US
63293, US, ARIN, FACEBOOK-OFFNET - Facebook, Inc., US

To discover all domains hosted within target ASNs, use the following option:

$ amass.netdomains -asn 13374,14618

To investigate target CIDRs, use this option:

$ amass.netdomains -cidr 192.184.113.0/24,104.154.0.0/15

For specific IPs or address ranges, use this option:

$ amass.netdomains -addr 192.168.1.44,192.168.2.1-64

By default, port 443 will be checked for certificates, but the ports can be changed as follows:

$ amass.netdomains -cidr 192.168.1.0/24 -p 80,443,8080

Create enlightening network graph visualizations that provide structure to the information you gather. This tool requires an input file generated by the amass '-do' flag.

Switches for outputting the DNS and infrastructure findings as a network graph:

Have amass send all the DNS and infrastructure information gathered to a graph database. This tool requires an input file generated by the amass '-do' flag.

$ amass.db -neo4j neo4j:DoNotUseThisPassword@localhost:7687 -i data_ops.json

If you are using the amass package within your own Go code, be sure to properly seed the default pseudo-random number generator:

import(
    "fmt"
    "math/rand"
    "time"

    "github.com/OWASP/Amass/amass"
)

func main() {
    rand.Seed(time.Now().UTC().UnixNano())

    enum := amass.NewEnumeration()

    go func() {
        for result := range enum.Output {
            fmt.Println(result.Name)
        }
    }()

    enum.AddDomain("example.com")
    enum.Start()
}

1. Output your Amass enumeration data using the '-do' flag:

$ amass -v -ip --active -brute -do owasp.json -d owasp.org

2. Convert the Amass data into a Maltego graph table CSV file:

$ amass.viz -i owasp.json --maltego owasp.csv

3. Import the CSV file with the correct Connectivity Table settings:

4. All the Amass findings will be brought into your Maltego Graph:

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Presented at Facebook (and shared publically) for the Sept. 2018 OWASP London Chapter meeting: