high
8.7
CWE
119 863
Advisory Published
CVE Published
Updated

CVE-2021-22543: Improper memory handling in Linux KVM

First published: Tue May 18 2021(Updated: )

A flaw was found in the Linux kernel’s KVM implementation, where improper handing of the VM_IO|VM_PFNMAP VMAs in KVM bypasses RO checks and leads to pages being freed while still accessible by the VMM and guest. This flaw allows users who can start and control a VM to read/write random pages of memory, resulting in local privilege escalation. The highest threat from this vulnerability is to confidentiality, integrity, and system availability.

Credit: cve-coordination@google.com cve-coordination@google.com cve-coordination@google.com

Affected SoftwareAffected VersionHow to fix
redhat/kernel<0:2.6.32-754.48.1.el6
0:2.6.32-754.48.1.el6
redhat/kernel-rt<0:3.10.0-1160.45.1.rt56.1185.el7
0:3.10.0-1160.45.1.rt56.1185.el7
redhat/kernel<0:3.10.0-1160.45.1.el7
0:3.10.0-1160.45.1.el7
redhat/kernel<0:3.10.0-327.101.1.el7
0:3.10.0-327.101.1.el7
redhat/kernel<0:3.10.0-514.93.1.el7
0:3.10.0-514.93.1.el7
redhat/kernel<0:3.10.0-693.94.1.el7
0:3.10.0-693.94.1.el7
redhat/kernel<0:3.10.0-957.84.1.el7
0:3.10.0-957.84.1.el7
redhat/kernel<0:3.10.0-1062.59.1.el7
0:3.10.0-1062.59.1.el7
redhat/kernel-rt<0:4.18.0-305.12.1.rt7.84.el8_4
0:4.18.0-305.12.1.rt7.84.el8_4
redhat/kernel<0:4.18.0-305.12.1.el8_4
0:4.18.0-305.12.1.el8_4
redhat/kernel<0:4.18.0-147.52.1.el8_1
0:4.18.0-147.52.1.el8_1
redhat/kernel-rt<0:4.18.0-193.64.1.rt13.115.el8_2
0:4.18.0-193.64.1.rt13.115.el8_2
redhat/kernel<0:4.18.0-193.64.1.el8_2
0:4.18.0-193.64.1.el8_2
redhat/redhat-virtualization-host<0:4.3.19-20211013.0.el7_9
0:4.3.19-20211013.0.el7_9
redhat/redhat-virtualization-host<0:4.4.7-20210804.0.el8_4
0:4.4.7-20210804.0.el8_4
redhat/kernel<5.13
5.13
IBM Cloud Pak for Security (CP4S)<=1.7.2.0
IBM Cloud Pak for Security (CP4S)<=1.7.1.0
IBM Cloud Pak for Security (CP4S)<=1.7.0.0
debian/linux
5.10.223-1
5.10.226-1
6.1.123-1
6.1.128-1
6.12.12-1
6.12.13-1
Linux Kernel=2021-05-18
Fedora=33
Fedora=34
Debian=9.0
All of
netapp h410c firmware
netapp h410c
All of
netapp h300s firmware
netapp h300s
All of
NetApp H500S Firmware
netapp h500s
All of
netapp h700s firmware
netapp h700s
All of
netapp h300e firmware
netapp h300e
All of
netapp h500e firmware
netapp h500e
All of
netapp h700e firmware
netapp h700e
All of
netapp h410s firmware
netapp h410s
netapp cloud backup
netapp solidfire baseboard management controller firmware
netapp baseboard management controller h410c firmware
netapp baseboard management controller h410c
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h300s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h500s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h700s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h300e
netapp baseboard management controller h500e firmware
netapp baseboard management controller h500e
netapp baseboard management controller h700e firmware
netapp baseboard management controller h700e
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h410s

Remedy

Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2021-22543?

    CVE-2021-22543 has been assigned a high severity rating due to its potential impact on system integrity and confidentiality.

  • How do I fix CVE-2021-22543?

    To fix CVE-2021-22543, upgrade to the latest kernel versions as specified by the vendor for your system.

  • Which systems are affected by CVE-2021-22543?

    CVE-2021-22543 affects multiple versions of the Linux kernel, particularly those from Red Hat and other distributions such as Fedora and Debian.

  • What can be exploited in CVE-2021-22543?

    CVE-2021-22543 can be exploited by users who control a virtual machine, allowing them to read or write memory that should be restricted.

  • Is there a patch available for CVE-2021-22543?

    Yes, patches are available and users should apply them based on the specific kernel version they are using.

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