CVE-2021-22543

8.7 highEPSS 0.7%

High (8.7). 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.

Severity

CVSS 4.0

8.7 high

CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L

CVSS 3.1

7.8 high

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.7% chance of exploitation in the next 30 days; higher than 51% of CVEs (scores of 2026-10-31)
CWE: CWE-119
Published: 2021-05-26
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

debian:debian_linux
fedoraproject:fedora
linux:linux_kernel
netapp:cloud_backup
netapp:h300e_firmware
netapp:h300s_firmware
netapp:h410c_firmware
netapp:h410s_firmware
netapp:h500e_firmware
netapp:h500s_firmware
netapp:h700e_firmware
netapp:h700s_firmware
netapp:solidfire_baseboard_management_controller_firmware

References

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