Linux · Linux Kernel · CVE-2023-46813
**Name of the Vulnerable Software and Affected Versions**
Linux kernel versions prior to 6.5.9
**Description**
The issue is caused by errors in synchronization when using a shared resource, potentially allowing an attacker to execute arbitrary code. It involves incorrect access checking in the #VC handler and instruction emulation of the SEV-ES emulation of MMIO accesses, which could lead to arbitrary write access to kernel memory and thus privilege escalation. This depends on a race condition through which userspace can replace an instruction before the #VC handler reads it.
**Recommendations**
For Linux kernel versions prior to 6.5.9, update to version 6.5.9 or later to resolve the issue. As a temporary workaround, consider restricting access to MMIO registers to minimize the risk of exploitation. Avoid using the #VC handler and SEV-ES emulation of MMIO accesses in sensitive operations until the issue is resolved.