High severity · published May 26, 2021
CVE-2021-22543
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…
7.8
CVSS
0.7%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 51% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2021-05-18 · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
9.0 · source: NVD
FE
Fedora · Fedoraproject
33; 34 · source: NVD
HF
H300e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H300s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410c Firmware · Netapp
All versions, or not specified · source: NVD
HF
H410s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H500s Firmware · Netapp
All versions, or not specified · source: NVD
HF
H700e Firmware · Netapp
All versions, or not specified · source: NVD
HF
H700s Firmware · Netapp
All versions, or not specified · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22543
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22543
Mailing List
http://www.openwall.com/lists/oss-security/2021/06/26/1
Exploit
https://github.com/google/security-research/security/advisories/GHSA-7wq5-phmq-m584
Mailing List
https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html
Mailing List
https://lists.debian.org/debian-lts-announce/2021/12/msg00012.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4G5YBUVEPHZYXMKNGBZ3S6INFCTEEL4E/
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ROQIXQB7ZAWI3KSGSHR6H5RDUWZI775S/
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