CVE-2021-22543: Improper memory handling in Linux KVM

An issue was discovered in Linux: KVM through Improper handling of VMIO|VMPFNMAP vmas in KVM can bypass RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users with the ability to start and control a VM to read/write random pages of memory and can result in local privilege escalation.

An issue was discovered in the Linux: KVM through Improper handling of VMIO|VMPFNMAP vmas in KVM can bypass RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users with the ability to start and control a VM to read/write random pages of memory and can result in local privilege escalation.

References:

https://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584 http://www.openwall.com/lists/oss-security/2021/05/26/3 http://www.openwall.com/lists/oss-security/2021/05/26/4 http://www.openwall.com/lists/oss-security/2021/05/26/5

— Red Hat

Linux Kernel could allow a local authenticated attacker to gain elevated privileges on the system, caused by improper handling of VMIO|VMPFNMAP vmas in KVM. By sending a specially-crafted request, an authenticated attacker could exploit this vulnerability to gain elevated privileges to start and control a VM to read/write random pages of memory.

— IBM