CVE-2018-15594

arch/x86/kernel/paravirt.c en el kernel de Linux en versiones anteriores a la 4.18.1 maneja incorrectamente algunas llamadas indirectas, lo que hace que sea más fácil para los atacantes realizar ataques Spectre-v2 contra guests paravirtuales.

It was found that paravirt_patch_call/jump() functions in the arch/x86/kernel/paravirt.c in the Linux kernel mishandles certain indirect calls, which makes it easier for attackers to conduct Spectre-v2 attacks against paravirtualized guests.

It was discovered that memory present in the L1 data cache of an Intel CPU core may be exposed to a malicious process that is executing on the CPU core. This vulnerability is also known as L1 Terminal Fault (L1TF). A local attacker could use this to expose sensitive information (memory from the kernel or other processes). It was discovered that the paravirtualization implementation in the Linux kernel did not properly handle some indirect calls, reducing the effectiveness of Spectre v2 mitigations for paravirtual guests. A local attacker could use this to expose sensitive information. Various other issues were also addressed.