Thursday, February 18, 2010

Screen Unlock Meterpreter Script

Just released a meterpreter script that can be used to unlock the screen of a windows system. The script needs SYSTEM privileges and patches the msv1_0.dll loaded by lsass.exe so that every password will be accepted to unlock the screen. (the patch can also be undone to get back to normal behavior). Currently Windows XP SP2 and SP3 are supported.
The idea for this technique was first published by Metlstorm used for the winlockpwn tool performing the patch via firewire access to a machine.

I think it might be good for some demonstration purposes.


  1. Nice. -- Video demo? :)

  2. very useful! thanks for sharing.

  3. meterpreter > sysinfo
    Computer: XPSP2
    OS : Windows XP (Build 2600, Service Pack 2).
    Arch : x86
    Language: en_US
    meterpreter > run screen_unlock
    [*] OS 'Windows XP (Build 2600, Service Pack 2).' found in known targets
    [-] found signature does not match

  4. I updated the script, it now works on some versions of Vista + 7 and supports more versions of XP by using relative offsets.

  5. Mark Baggett has created a nice video for PaulDotCom showing how to use the script: