Physical Attacks

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BIOS Password Recovery and System Security

Resetting the BIOS can be achieved in several ways. Most motherboards include a battery that, when removed for around 30 minutes, will reset the BIOS settings, including the password. Alternatively, a jumper on the motherboard can be adjusted to reset these settings by connecting specific pins.

For situations where hardware adjustments are not possible or practical, software tools offer a solution. Running a system from a Live CD/USB with distributions like Kali Linux provides access to tools like killCmos and CmosPWD, which can assist in BIOS password recovery.

In cases where the BIOS password is unknown, entering it incorrectly three times will typically result in an error code. This code can be used on websites like https://bios-pw.org to potentially retrieve a usable password.

UEFI Security

For modern systems using UEFI instead of traditional BIOS, the tool chipsec can be utilized to analyze and modify UEFI settings, including the disabling of Secure Boot. This can be accomplished with the following command:

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

RAM Analysis and Cold Boot Attacks

RAM retains data briefly after power is cut, usually for 1 to 2 minutes. This persistence can be extended to 10 minutes by applying cold substances, such as liquid nitrogen. During this extended period, a memory dump can be created using tools like dd.exe and volatility for analysis.

Direct Memory Access (DMA) Attacks

INCEPTION is a tool designed for physical memory manipulation through DMA, compatible with interfaces like FireWire and Thunderbolt. It allows for bypassing login procedures by patching memory to accept any password. However, it's ineffective against Windows 10 systems.

Live CD/USB for System Access

Changing system binaries like sethc.exe or Utilman.exe with a copy of cmd.exe can provide a command prompt with system privileges. Tools such as chntpw can be used to edit the SAM file of a Windows installation, allowing password changes.

Kon-Boot is a tool that facilitates logging into Windows systems without knowing the password by temporarily modifying the Windows kernel or UEFI. More information can be found at https://www.raymond.cc.

Handling Windows Security Features

Boot and Recovery Shortcuts

• Supr: Access BIOS settings.
• F8: Enter Recovery mode.
• Pressing Shift after the Windows banner can bypass autologon.

BAD USB Devices

Devices like Rubber Ducky and Teensyduino serve as platforms for creating bad USB devices, capable of executing predefined payloads when connected to a target computer.

Volume Shadow Copy

Administrator privileges allow for the creation of copies of sensitive files, including the SAM file, through PowerShell.

Bypassing BitLocker Encryption

BitLocker encryption can potentially be bypassed if the recovery password is found within a memory dump file (MEMORY.DMP). Tools like Elcomsoft Forensic Disk Decryptor or Passware Kit Forensic can be utilized for this purpose.

Social Engineering for Recovery Key Addition

A new BitLocker recovery key can be added through social engineering tactics, convincing a user to execute a command that adds a new recovery key composed of zeros, thereby simplifying the decryption process.