CVSS 3.1
8.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HCVE-2021-4093
High (8.8). EPSS 0.4% chance of exploitation in the next 30 days.
A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES). A KVM guest using SEV-ES can trigger out-of-bounds reads and writes in the host kernel via a malicious VMGEXIT for a string I/O instruction (for example, outs or ins) using the exit reason SVM_EXIT_IOIO. This issue results in a crash of the entire system or a potential guest-to-host escape scenario.
Severity
- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-125, CWE-787
- Published
- Modified
- Record from
- the NVD, synced
Affected
- canonical:ubuntu_linux
- fedoraproject:fedora
- linux:linux_kernel
- redhat:enterprise_linux