HOMEVULNERABILITIESCVE-2021-22543
HIGH

CVE-2021-22543

CWE-119Published: May 26, 2021· Updated: Jun 17, 2026

7.8
CVSS v3.1

Official Description

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.

NVD Source

Technical Analysis

CVE-2021-22543 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.8.

From a weakness classification perspective (CWE-119): Buffer overflow vulnerabilities can lead to arbitrary code execution or denial of service by corrupting adjacent memory.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

Debian1 product(s)
debian linux
Fedora1 product(s)
fedora
Linux1 product(s)
linux kernel
netapp18 product(s)
h410c firmwareh410ch300s firmwareh300sh500s firmwareh500sh700s firmwareh700sh300e firmwareh300eh500e firmwareh500e+6
Source: NVD CPE · 22 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

ADVISORYhttps://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584
ADVISORYhttps://lists.debian.org/debian-lts-announce/2021/10/msg00010.html
ADVISORYhttps://lists.debian.org/debian-lts-announce/2021/12/msg00012.html
ADVISORYhttps://security.netapp.com/advisory/ntap-20210708-0002/
ADVISORYhttps://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584
ADVISORYhttps://lists.debian.org/debian-lts-announce/2021/10/msg00010.html
ADVISORYhttps://lists.debian.org/debian-lts-announce/2021/12/msg00012.html
ADVISORYhttps://security.netapp.com/advisory/ntap-20210708-0002/

All References (14)

→
http://www.openwall.com/lists/oss-security/2021/06/26/1Mailing List
→
https://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584Exploit · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2021/10/msg00010.htmlMailing List · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.htmlMailing List · Third Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4G5YBUVEPHZYXMKNGBZ3S6INFCTEEL4E/
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ROQIXQB7ZAWI3KSGSHR6H5RDUWZI775S/
→
https://security.netapp.com/advisory/ntap-20210708-0002/Third Party Advisory
→
http://www.openwall.com/lists/oss-security/2021/06/26/1Mailing List
→
https://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584Exploit · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2021/10/msg00010.htmlMailing List · Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.htmlMailing List · Third Party Advisory
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4G5YBUVEPHZYXMKNGBZ3S6INFCTEEL4E/
→
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ROQIXQB7ZAWI3KSGSHR6H5RDUWZI775S/
→
https://security.netapp.com/advisory/ntap-20210708-0002/Third Party Advisory

Quick Facts

CVE IDCVE-2021-22543
CVSS Score7.8 / 10
SeverityHIGH
WeaknessCWE-119
CISA KEVNo
Affected4 vendor(s)
PublishedMay 26, 2021

Related CVEs (CWE-119)

CVE-2011-0994
10.0
CVE-2011-1848
10.0
CVE-2011-0056
10.0
CVE-2011-0058
10.0
CVE-2011-0054
10.0
CVE-2011-1728
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2021-22543 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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