CVE-2023-4155

A flaw was found in KVM AMD Secure Encrypted Virtualization (SEV) in the Linux kernel. A KVM guest using SEV-ES or SEV-SNP with multiple vCPUs can trigger a double fetch race condition vulnerability and invoke the VMGEXIT handler recursively. If an attacker manages to call the handler multiple times, they can trigger a stack overflow and cause a denial of service or potentially guest-to-host escape in kernel configurations without stack guard pages (CONFIG_VMAP_STACK).

Red Hat Enterprise Linux 6 and 7 are not affected by this flaw, as they did not include support for KVM AMD Secure Encrypted Virtualization (SEV). Note: AMD SEV is currently provided as a Technology Preview in RHEL 8, therefore, it is unsupported for production use. For additional details see https://access.redhat.com/articles/4491591 and https://access.redhat.com/support/offerings/techpreview.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.