The ZeroPeril team discovered an issue with the AMD Platform Security Processor (PSP) which results in a vulnerability that opens memory allocation to exploitation. The purpose of the PSP chip is to manage the internal security of the CPU, and all internal components in a hardware driver approach that operates to control and distribute communication between the components and the CPU. The vulnerability occurs within the PSP's allocations to memory space (the systems' RAM). The team confirmed that an attacker may be able to send a request to the driver to allocate memory. If the request is for an amount of memory that is smaller than the set minimum allocation size within windows, the process will be allocated the minimum allocation. An example of what I mean by the prior statement is, if say, the memory request is for 10 bytes of memory space, and the minimum allocation size allowed by windows is 2048 bytes (2KB) then the memory request will be filled with the full 2KB of memory, when all was requested was 10 bytes.

So what does that prior assessment mean? It means that an attacker can scavenge through idle memory space, this is possible because Microsoft doesn't have a cleanup process for unallocated memory. Such memory may have been used previously for other task(s). Unallocated memory can and does store files from previously run tasks, thus leaving whatever leftover memory contents is present, available to be accessed by any other actor. This could be anything from documents accessed through an office suite, to login credentials stored in an application instance, such as credentials used for banking in a web browser.

Our recommendation is to patch as soon as possible for affected devices as AMD has released a patch named. This can be done by confirming Microsoft update has updated the AMD Chipset Driver to version 3.08.17.735.