Hypervisor-assisted Atomic Memory Acquisition in Modern Systems

Abstract

Reliable memory acquisition is essential to forensic analysis of a cyber-crime. Various methods of memory acquisition have been proposed, ranging from tools based on a dedicated hardware to software only solutions. Recently, a hypervisor-based method for memory acquisition was proposed (Qi et al., 2017; Martignoni et al., 2010). This method obtains a reliable (atomic) memory image of a running system. The method achieves this by making all memory pages non-writable until they are copied to the memory image, thus preventing uncontrolled modification of these pages. Unfortunately, the proposed method has two deficiencies: (1) the method does not support multiprocessing and (2) the method does not support modern operating systems featuring address space layout randomization (ASLR). We describe a hypervisor-based memory acquisition method that solves the two aforementioned deficiencies. We analyze the memory usage and performance of the proposed method.