How do you acquire and analyze volatile memory from mobile devices?

Mobile devices typically use integrated circuits for memory, combining both volatile (RAM) and non-volatile (flash) storage. RAM in mobile devices stores running applications and process information, crucial for forensic analysis. Understanding the specifics, such as whether a device uses LPDDR3 or LPDDR4 RAM, can influence how memory is accessed and dumped, affecting both the tools used and the data's integrity.

Memory acquisition from mobile devices can be performed via physical acquisition directly from the device or through logical acquisition using backup services. Physical acquisition often requires root access or bootloader unlocking to directly image the device’s memory. For example, using JTAG or chip-off techniques allows deeper access to volatile and non-volatile memory, essential for extracting real-time operation data and decryption keys.

Mobile Acquisition has 2 terms Hot and Cold. Hot - when the device is running and is forensically preserved before the device is turned off. Cold - when the device is received in a turned off state. Forensic preservation is done after turning on the device. Hot collection can provide a plethora of information including caches, cookies, passwords etc, which is very useful for immediate analysis. Hot devices are difficult to perform brute force as their could be anti forensic tool in background. Cold collection does not have all volatile data but the modern operating systems are designed to restart the device from the last time the device was turned off thereby giving clues during analysis. Brute forcing is easier in this case.

Dead acquisition is performed when the device is powered off or rebooted. Memory dumps are obtained by exploiting vulnerabilities in the boot process or the firmware. Since the device is not operational, the risk of altering the data state is minimized. This method often requires advanced technical skills and knowledge of specific vulnerabilities. PCILeech uses PCIe hardware devices to read and write target system memory via Direct Memory Access (DMA). PCILeech is a tool that is commonly used for hardware security.

Tools like Cellebrite UFED and Oxygen Forensic Detective are commonly used for acquiring memory from mobile devices. These tools support a wide range of devices and can bypass certain security features to access memory. For instance, UFED can perform advanced unlocking and extraction on many Android and iOS devices, allowing for comprehensive memory dumps.

Indeed iMAT allows investigators to perform memory dumps on jailbroken iOS devices, providing a method to capture volatile memory for forensic analysis. It is particularly useful for devices that have been jailbroken to bypass Apple's security restrictions. Checkm8 is a bootrom exploit that targets iOS devices with A5 to A11 chips. It puts the device in Device Firmware Upgrade (DFU) mode and sends a payload that enables memory readout. Checkm8 exploits a vulnerability in the bootrom of certain iOS devices, allowing investigators to bypass security features and perform memory acquisition. This method is effective for devices that fall within the specified chip range.

For analyzing mobile device memory, tools such as Volatility and Magnet RAM Capture are adapted to handle mobile formats. Volatility, with the right plugins, can analyze Android and iOS memory dumps to recover artifacts like running processes, network information, and open files. This analysis is vital for reconstructing user actions and understanding malware presence.

Data types typically analyzed in mobile memory forensics include active apps, running processes, system logs, network connections, and user interactions. Extracting such data can reveal evidence of app usage, communications, or malicious activities. For example, analyzing RAM could uncover encrypted messages in memory that were displayed on the screen at the time of acquisition, despite being stored encrypted on disk.

When dealing with mobile memory forensics, consider the legal and ethical implications, particularly around user privacy and data protection laws. Ensure all forensic activities are justified, documented, and carried out under appropriate legal authority. Additionally, keeping up with the latest developments in mobile operating systems and security features is crucial, as these constantly evolve, affecting how memory can be acquired and analyzed.