CVE-2021-4093 — Out-of-bounds Read in Kernel
Severity
8.8HIGHNVD
EPSS
0.1%
top 74.53%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedFeb 18
Latest updateFeb 19
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitability: 2.0 | Impact: 6.0
Affected Packages3 packages
Also affects: Fedora 35, Ubuntu Linux 20.04, 21.10, Enterprise Linux 8.0
Patches
🔴Vulnerability Details
3GHSA▶
GHSA-2vg6-vx3w-m2r4: A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES)↗2022-02-19
CVEList▶
CVE-2021-4093: A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES)↗2022-02-18
OSV▶
CVE-2021-4093: A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtualization-Encrypted State (SEV-ES)↗2022-02-18
📋Vendor Advisories
4Microsoft▶
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 kern↗2022-02-08
Debian▶
CVE-2021-4093: linux - A flaw was found in the KVM's AMD code for supporting the Secure Encrypted Virtu...↗2021