Pentesting

Physical Attacks

BIOS password

The battery

Most of the motherbords have a battery. I you remove it 30min the settings of the BIOS will be restarted (password included).

Jumper CMOS

Most of the motherboards have a jumper that can restart the settings. This jumper connects a central pin with another, if you connect thoses pins the motherbord will be reseted.

Live Tools

If you could run for example a Kali Linux from a Live CD/USB you could use tools like killCmos or CmosPWD (this last one is included in Kali) you could try to recover the password of the BIOS.

Online BIOS password recovery

Put the password of the BIOS 3 times wrong, then the BIOS will show an error message and it will be blocked. Visit the page https://bios-pw.org and introduce the error code shown by the BIOS and you could be lucky and get a valid password (the same search could show you different passwords and more than 1 could be valid).

UEFI

To check the settings of the UEFI and perform some kind of attack you should try chipsec. Using this tool you could easily disable the Secure Boot:

python chipsec_main.py -module exploits.secure.boot.pk

RAM

Cold boot

The RAM memory is persistent from 1 to 2 minutes from the time the computer is powered off. If you apply cold (liquid nitrogen, for example) on the memory card you can extend this time up to 10 minutes.

Then, you can do a memory dump (using tools like dd.exe, mdd.exe, Memoryze, win32dd.exe or DumpIt) to analyze the memory.

You should analyze the memory using volatility.

INCEPTION

Inception is a physical memory manipulation and hacking tool exploiting PCI-based DMA. The tool can attack over FireWire, Thunderbolt, ExpressCard, PC Card and any other PCI/PCIe HW interfaces. Connect your computer to the victim computer over one of those interfaces and INCEPTION will try to patch the pyshical memory to give you access.

If INCEPTION succeeds, any password introduced will be vaid.

It doesn't work with Wndows10.

Live CD/USB

Sticky Keys and more

  • SETHC: sethc.exe is invoked when SHIFT is pressed 5 times

  • UTILMAN: Utilman.exe is invoked by pressing WINDOWS+U

  • OSK: osk.exe is invoked by pressing WINDOWS+U, then launching the on-screen keyboard

  • DISP: DisplaySwitch.exe is invoked by pressing WINDOWS+P

These binaries are located inside C:\Windows\System32. You can change any of them for a copy of the binary cmd.exe (also in the same folder) and any time that you invoke any of those binaries a command prompt as SYSTEM will appear.

Modifying SAM

You can use the tool chntpw to modify the SAM file of a mounted Windows filesystem. Then, you could change the password of the Administrator user, for example. This tool is available in KALI.

chntpw -h
chntpw -l <path_to_SAM>

Inside a Linux system you could modify the /etc/shadow or /etc/passwd file.

Kon-Boot

Kon-Boot is one of the best tools around which can log you into Windows without knowing the password. It works by hooking into the system BIOS and temporarily changing the contents of the Windows kernel while booting (new versions work also with UEFI). It then allows you to enter anything as the password during login. The next time you start the computer without Kon-Boot, the original password will be back, the temporary changes will be discarded and the system will behave as if nothing has happened. Read More: https://www.raymond.cc/blog/login-to-windows-administrator-and-linux-root-account-without-knowing-or-changing-current-password/

It is a live CD/USB that can patch the memory so you won't need to know the password to login. Kon-Boot also performs the StickyKeys trick so you could press Shift 5 times to get an Administrator cmd.

Running Windows

Initial shortcuts

Booting shortcuts

  • supr - BIOS

  • f8 - Recovery mode

  • supr - BIOS ini

  • f8 - Recovery mode

  • Shitf (after the windows banner) - Go to login page instead of autologon (avoid autologon)

BAD USBs

Rubber Ducky tutorials

Teensyduino

There are also tons of tutorials about how to create your own bad USB.

Volume Shadow Copy

With administrators privileges and powershell you could make a copy of the SAM file. See this code.

Bypassing Bitlocker

Bitlocker uses 2 passwords. The one used by the user, and the recovery password (48 digits).

If you are lucky and inside the current session of Windows exists the file C:\Windows\MEMORY.DMP (It is a memory dump) you could try to search inside of it the recovery password. You can get this file and a copy of the filesytem and then use Elcomsoft Forensic Disk Dercyptor to get the content (this will only work if the password is inside the memory dump). You coud also force the memory dump using NotMyFault of Sysinternals, but this will reboot the system and has to be executed as Administrator.

You could also try a bruteforce attack using Passware Kit Forensic.

Social Engineering

Finally, you could make the user add a new recovery password making him executed as administrator:

schtasks /create /SC ONLOGON /tr "c:/windows/system32/manage-bde.exe -protectors -add c: -rp 000000-000000-000000-000000-000000-000000-000000-000000" /tn tarea /RU SYSTEM /f

This will add a new recovery key (composed of 48 zeros) in the next login.

To check the valid recovery keys you can execute:

manage-bde -protectors -get c: