Cryo-Mechanical RAM Content Extraction Against Modern Embedded Systems

Abstract

Cryogenic mechanical memory extraction provides a means to obtain a device's volatile memory content at run-time. Numerous prior works has have demonstrated successful exploitation of the Memory Remanence Effect on modern computers and mobile devices. While this approach is arguably one of the most direct paths to reading a target device's physical RAM content, several significant limitations exist. For example, prior works were done either on removable memory with standardized connectors, or with the use of a custom kernel/bootloader. We present a generalized and automated system that performs reliable RAM content extraction against modern embedded devices. Our cryo-mechanical apparatus is built using low-cost hardware that is widely available, and supports target devices using single or multiple DDR1|2|3 memory modules. We discuss several novel techniques and hardware modifications that allow our apparatus to exceed the spatial and temporal precision required to reliably perform memory extraction against modern embedded systems that have memory modules soldered directly onto the PCB, and use custom memory controllers that spread bits of each word of memory across multiple physical RAM chips.