SB2022021843 - Out-of-bounds read in Linux kernel
Published: February 18, 2022
Security Bulletin ID
SB2022021843
Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Out-of-bounds read (CVE-ID: CVE-2021-4093)
The vulnerability allows a local user to escalate privileges on the system.
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.
Remediation
Install update from vendor's website.