Linux Kernel Gets Patch For New SpectreRSB Vulnerability

Earlier this week SpectreRSB was revealed by University of California researchers as a new Spectre V2 like attack affecting modern processors. A Linux kernel patch is in the works for starting to mitigate SpectreRSB.

The RSB in this context is with regards to the Return Stack Buffer that is targeted in this latest speculative execution issue. The researchers found with this vulnerability they could exploit private data supposed to be protected by Intel's Software Guard Extensions (SGX) and that the return stack buffer attacks could be cross-process or inter-VM.

Jiri Kosina of SUSE published an initial SpectreRSB Linux kernel patch. With the initial patch it mitigates userspace-userspace attacks but does not address the potential userspace-kernelspace attack vector in its current form.

This SpectreRSB Linux kernel patch currently undergoing review can be found on the kernel mailing list.