Fierce - Semi-Lightweight Scanner That Helps Locate Non-Contiguous IP Space And Hostnames Against Specified Domains

Fierce is a semi-lightweight scanner that helps locate non-contiguous IP space and hostnames against specified domains.

It's really meant as a pre-cursor to nmap, unicornscan, nessus, nikto, etc, since all of those require that you already know what IP space you are looking for.

This does not perform exploitation and does not scan the whole internet indiscriminately. It is meant specifically to locate likely targets both inside and outside a corporate network.

Because it uses DNS primarily you will often find mis-configured networks that leak internal address space. That's especially useful in targeted malware.

Options:

-connect    Attempt to make http connections to any non RFC1918
     (public) addresses.  This will output the return headers but
     be warned, this could take a long time against a company with
     many targets, depending on network/machine lag.  I wouldn't
     recommend doing this unless it's a small company or you have a
     lot of free time on your hands (could take hours-days).
     Inside the file specified the text "Host:\n" will be replaced
     by the host specified. Usage:
 
 perl fierce.pl -dns example.com -connect headers.txt
 
 -delay      The number of seconds to wait between lookups.
 -dns        The domain you would like scanned.
 -dnsfile    Use DNS servers provided by a file (one per line) for
             reverse lookups (brute force).
 -dnsserver  Use a particular DNS server for reverse lookups
     (probably should be the DNS server of the target).  Fierce
     uses your DNS server for the initial SOA query and then uses
     the target's DNS server for all additional queries by default.
 -file       A file you would like to output to be logged to.
 -fulloutput When combined with -connect this will output everything
     the webserver sends back, not just the HTTP headers.
 -help       This screen.
 -nopattern  Don't use a search pattern when looking for nearby
     hosts.  Instead dump everything.  This is really noisy but
     is useful for finding other domains that spammers might be
     using.  It will also give you lots of false positives,
     especially on large domains.
 -range      Scan an internal IP range (must be combined with
     -dnsserver).  Note, that this does not support a pattern
     and will simply output anything it finds.  Usage:
 
 perl fierce.pl -range 111.222.333.0-255 -dnsserver ns1.example.co
 
 -search     Search list.  When fierce attempts to traverse up and
     down ipspace it may encounter other servers within other
     domains that may belong to the same company.  If you supply a
     comma delimited list to fierce it will report anything found.
     This is especially useful if the corporate servers are named
     different from the public facing website.  Usage:
 
 perl fierce.pl -dns examplecompany.com -search corpcompany,blahcompany
 
     Note that using search could also greatly expand the number of
     hosts found, as it will continue to traverse once it locates
     servers that you specified in your search list.  The more the
     better.
 -suppress   Suppress all TTY output (when combined with -file).
 -tcptimeout Specify a different timeout (default 10 seconds).  You
     may want to increase this if the DNS server you are querying
     is slow or has a lot of network lag.
 -threads  Specify how many threads to use while scanning (default
   is single threaded).
 -traverse   Specify a number of IPs above and below whatever IP you
     have found to look for nearby IPs.  Default is 5 above and
     below.  Traverse will not move into other C blocks.
 -version    Output the version number.
 -wide       Scan the entire class C after finding any matching
     hostnames in that class C.  This generates a lot more traffic
     but can uncover a lot more information.
 -wordlist   Use a seperate wordlist (one word per line).  Usage:
 
 perl fierce.pl -dns examplecompany.com -wordlist dictionary.txt

fierce Usage Example

[email protected]:~# fierce -dns example.com
   DNS Servers for example.com:
     b.iana-servers.net
     a.iana-servers.net
 
 Trying zone transfer first...
 Testing b.iana-servers.net
     Request timed out or transfer not allowed.
 Testing a.iana-servers.net
     Request timed out or transfer not allowed.
 
 Unsuccessful in zone transfer (it was worth a shot)
 Okay, trying the good old fashioned way... brute force
 
 Checking for wildcard DNS...
 Nope. Good.
 Now performing 2280 test(s)...