Ways to bypass / reset passwords on various OS's:

Bypassing

in Windows:

• kon-boot
• eEye SysRQ2
• other bootkits

in Linux:

• kon-boot
• single-user mode, combined with any backdoor
  • cd /var/tmp; cp /bin/bash backdoor; chmod 4755 backdoor
    (later) /var/tmp/backdoor -p
    id -u

reset Windows password

• boot into a Linux CD (eg. BackTrack), and replace an important exe with cmd.exe:
  • c:\windows\system32\sethc.exe — press the shift key 5 times to launch it during login prompt
  • c:\windows\system32\utilman.exe — press Windows-U to launch it during login prompt (video :))
    (a different way to do this)
  • screensaver
• install srvany.exe

reset Linux password