CVE-2023-4155: Fedoraproject Fedora

Medium severity, CVSS 5.6. EPSS: 0.2% chance of exploitation in the next 30 days.

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`).

Affected products

• Fedoraproject Fedora: version 37 only; version 38 only
• Linux Linux Kernel: affected versions not specified
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only

Published 2023-09-13. Last modified 2026-06-17.