CVE-2021-22543: Debian Linux

High severity, CVSS 7.8. EPSS: 0.7% chance of exploitation in the next 30 days.

An issue was discovered in Linux: KVM through Improper handling of VM_IO|VM_PFNMAP 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.

Affected products

• Debian Debian Linux: version 9.0 only
• Fedoraproject Fedora: version 33 only; version 34 only
• Linux Linux Kernel: version 2021-05-18 only
• Netapp Cloud Backup: affected versions not specified
• Netapp h300e Firmware: affected versions not specified
• Netapp h300s Firmware: affected versions not specified
• Netapp h410c Firmware: affected versions not specified
• Netapp h410s Firmware: affected versions not specified
• Netapp h500e Firmware: affected versions not specified
• Netapp h500s Firmware: affected versions not specified
• Netapp h700e Firmware: affected versions not specified
• Netapp h700s Firmware: affected versions not specified
• Netapp Solidfire Baseboard Management Controller Firmware: affected versions not specified

Published 2021-05-26. Last modified 2026-06-17.