CVE-2021-22543

mediumpriority · track · 31EPSS 0.007 · 51 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.66% (51st) EPSS

CVSS 4.6 · medium

Is it mine?

61 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

8.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.7

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v4.08.7highCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:Lsecondary · ENISA EU

v4.08.7highCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · cve-coordination@google.com

v4.05.7mediumCVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-119USprimaryCWE-119US

affected products (61)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Avaya Aura Experience Portalall versionscert_bundDEcpe:/a:avaya:aura_experience_portal:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Dell PowerProtect Data Domain <7.10.1.70all versionscert_bundDE
Dell PowerProtect Data Domain <7.13.1.40all versionscert_bundDE
Dell PowerProtect Data Domain <8.3.1.10all versionscert_bundDE
Dell PowerProtect Data Domain <8.4.0.0all versionscert_bundDE
Open Source CentOSall versionscert_bundDEcpe:/o:centos:centos:-
Open Source Linux Kernelall versionscert_bundDEcpe:/o:linux:linux_kernel:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat Enterprise Linux 7all versionscert_bundDEcpe:/o:redhat:enterprise_linux:7
Red Hat Enterprise Linux 8all versionscert_bundDEcpe:/o:redhat:enterprise_linux:8
Red Hat Virtualization 4all versionscert_bundDEcpe:/a:redhat:virtualization:4
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Dell PowerProtect Data Domain< 7.10.1.70cert_bundDE
Dell PowerProtect Data Domain< 7.13.1.40cert_bundDE
Dell PowerProtect Data Domain< 8.3.1.10cert_bundDE
Dell PowerProtect Data Domain< 8.4.0.0cert_bundDE

showing 20 of 61

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-0242Linux Kernel: Schwachstelle ermöglicht PrivilegieneskalationDeutsch2021-05-26csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um seine Privilegien zu erhöhen.
WID-SEC-W-2022-0243Linux Kernel: Schwachstelle ermöglicht PrivilegieneskalationDeutsch2021-06-27csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel, Red Hat Enterprise Linux und Red Hat Virtualization ausnutzen, um seine Privilegien zu erhöhen.
WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund NVD CVE.org MITRE

published 2021-05-26modified 2026-06-17

related (21,028)

Related entries.

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+21023 more

references (77)

External citations — patches, advisories, analysis.

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