Battering RAM

Am I impacted by this vulnerability?

Battering RAM can affect all systems using DDR4 memory, but is especially relevant for "confidential computing" workloads running in public cloud environments. Modern Intel and AMD x86 cloud processors feature built-in access control and memory encryption to keep private data safe, even from the company running the cloud.

Battering RAM needs physical access; is this a realistic attack vector?

Confidential computing aims to protect private data even from the cloud provider, using hardware-level access control and memory encryption. Even if someone accesses the memory, they should only see encrypted (garbled) data. Battering RAM uses a low-cost, custom-built memory interposer installed between the processor and memory to tamper with such encrypted memory.

What are Intel SGX and AMD SEV; who uses this technology?

Intel SGX and AMD SEV-SNP are two leading hardware-based trusted execution environments that enable secure cloud computations without needing to trust the cloud provider. They do this by enforcing strict access control and encrypting memory so that even if someone accesses it, they only see unreadable data.

How difficult is it to perform this attack in practice?

The main difficulty lies in setting up the system; installing the interposer, and mapping out unstable memory regions (see details in the academic paper). However, once installed, the interposer is simple and stable to operate and can be built at low cost ($50).

Can this be fixed by software or firmware updates?

No. Battering RAM uses a custom-built memory interposer that sits silently between the processor and memory. Our interposer can be dynamically enabled or disabled at runtime and remains invisible during system startup, passing all trust checks, such as those introduced for BadRAM. The interposer silently alters memory commands without detection, making the attack undetectable and unpatchable via software or firmware.