CVE-2021-33656: High severity Huawei Openeuler vulnerability

Published Jan 5, 2021
·
Updated

A flaw in the Linux Kernel console driver found. When setting font with malicious data by ioctl PIOFONT, kernel will write memory out of bounds. To trigger the vulnerability user need to have access to console driver like if text mode being used through a generic VGA standard display.

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/releases/5.10.127/vt-drop-old-font-ioctls.patch

Other sources

An out-of-bounds write flaw was found in the Linux kernel’s console driver functionality in the way a user triggers the ioctl PIOFONT with malicious data. This flaw allows a local user to crash or potentially escalate their privileges on the system.

When setting font with malicous data by ioctl cmd PIOFONT,kernel will write memory out of bounds.

Affected Software

113 affected componentsFixes available
redhat/kernel-rt<0:4.18.0-477.10.1.rt7.274.el8_8
0:4.18.0-477.10.1.rt7.274.el8_8
redhat/kernel<0:4.18.0-477.10.1.el8_8
0:4.18.0-477.10.1.el8_8
redhat/kernel<0:4.18.0-372.70.1.el8_6
0:4.18.0-372.70.1.el8_6
redhat/kernel<5.12
5.12
Huawei Openeuler=20.03
Huawei Openeuler=20.03-sp1
Huawei Openeuler=20.03-sp3
Linux Linux kernel<5.10.127
Debian Debian Linux=10.0
Openatom Openeuler=20.03
Openatom Openeuler=20.03-sp1
Openatom Openeuler=20.03-sp3
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1
ubuntu/linux-aws<4.4.0-1113.119
4.4.0-1113.119
ubuntu/linux-azure<4.15.0-1150.165~14.04.1
4.15.0-1150.165~14.04.1
ubuntu/linux-lts-xenial<4.4.0-234.268~14.04.1
4.4.0-234.268~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-234.268
4.4.0-234.268
ubuntu/linux-aws<4.4.0-1150.165
4.4.0-1150.165
ubuntu/linux-aws-hwe<4.15.0-1140.151~16.04.1
4.15.0-1140.151~16.04.1
ubuntu/linux-azure<4.15.0-1150.165~16.04.1
4.15.0-1150.165~16.04.1
ubuntu/linux-gcp<4.15.0-1135.151~16.04.2
4.15.0-1135.151~16.04.2
ubuntu/linux-hwe<4.15.0-192.203~16.04.1
4.15.0-192.203~16.04.1
ubuntu/linux-kvm<4.4.0-1114.124
4.4.0-1114.124
ubuntu/linux-oracle<4.15.0-1105.116~16.04.1
4.15.0-1105.116~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1083.90
4.4.0-1083.90
ubuntu/linux-fips*
ubuntu/linux<4.15.0-192.203
4.15.0-192.203
ubuntu/linux-aws<4.15.0-1140.151
4.15.0-1140.151
ubuntu/linux-aws-5.4<5.4.0-1084.91~18.04.1
5.4.0-1084.91~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1150.165
4.15.0-1150.165
ubuntu/linux-azure-5.4<5.4.0-1090.95~18.04.1
5.4.0-1090.95~18.04.1
ubuntu/linux-dell300x<4.15.0-1052.57
4.15.0-1052.57
ubuntu/linux-gcp-4.15<4.15.0-1135.151
4.15.0-1135.151
ubuntu/linux-gcp-5.4<5.4.0-1087.95~18.04.1
5.4.0-1087.95~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-125.141~18.04.1
5.4.0-125.141~18.04.1
ubuntu/linux-ibm-5.4<5.4.0-1032.36~18.04.1
5.4.0-1032.36~18.04.1
ubuntu/linux-kvm<4.15.0-1126.131
4.15.0-1126.131
ubuntu/linux-oracle<4.15.0-1105.116
4.15.0-1105.116
ubuntu/linux-oracle-5.4<5.4.0-1082.90~18.04.1
5.4.0-1082.90~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1069.79~18.04.1
5.4.0-1069.79~18.04.1
ubuntu/linux-raspi2<4.15.0-1118.126
4.15.0-1118.126
ubuntu/linux-snapdragon<4.15.0-1136.146
4.15.0-1136.146
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2079.84
4.15.0-2079.84
ubuntu/linux-azure-fips<4.15.0-2060.66
4.15.0-2060.66
ubuntu/linux-fips<4.15.0-1097.108
4.15.0-1097.108
ubuntu/linux-gcp-fips<4.15.0-2044.49
4.15.0-2044.49
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-125.141
5.4.0-125.141
ubuntu/linux-aws<5.4.0-1084.91
5.4.0-1084.91
ubuntu/linux-azure<5.4.0-1090.95
5.4.0-1090.95
ubuntu/linux-bluefield<5.4.0-1045.50
5.4.0-1045.50
ubuntu/linux-gcp<5.4.0-1087.95
5.4.0-1087.95
ubuntu/linux-gke<5.4.0-1081.87
5.4.0-1081.87
ubuntu/linux-gkeop<5.4.0-1052.55
5.4.0-1052.55
ubuntu/linux-ibm<5.4.0-1032.36
5.4.0-1032.36
ubuntu/linux-iot<5.4.0-1004.6
5.4.0-1004.6
ubuntu/linux-kvm<5.4.0-1074.79
5.4.0-1074.79
ubuntu/linux-oracle<5.4.0-1082.90
5.4.0-1082.90
ubuntu/linux-raspi<5.4.0-1069.79
5.4.0-1069.79
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.8*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.8*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.8*
ubuntu/linux-intel-5.13*
ubuntu/linux-oem-5.10*
ubuntu/linux-oem-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.11*
ubuntu/linux-oracle-5.13*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.8*
ubuntu/linux-aws-fips<5.4.0-1085.92+fips1
5.4.0-1085.92+fips1
ubuntu/linux-azure-fips<5.4.0-1090.95+fips1
5.4.0-1090.95+fips1
ubuntu/linux-fips<5.4.0-1060.68
5.4.0-1060.68
ubuntu/linux-gcp-fips<5.4.0-1087.95+fips1
5.4.0-1087.95+fips1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-raspi-realtime*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-477.10.1.rt7.274.el8_8
  2. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-477.10.1.el8_8
  3. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-372.70.1.el8_6
  4. Upgrade

    Upgrade redhat/Kernel to a version that resolves this vulnerability.

    Fixed in 5.12
  5. Upgrade

    Upgrade debian/linux to a version that resolves this vulnerability.

    Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1
  6. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1113.119
  7. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1150.165~14.04.1
  8. Upgrade

    Upgrade ubuntu/linux-lts-xenial to a version that resolves this vulnerability.

    Fixed in 4.4.0-234.268~14.04.1
  9. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 4.4.0-234.268
  10. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1150.165
  11. Upgrade

    Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-1140.151~16.04.1
  12. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1150.165~16.04.1
  13. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 4.15.0-1135.151~16.04.2
  14. Upgrade

    Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-192.203~16.04.1
  15. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.4.0-1114.124
  16. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1105.116~16.04.1
  17. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.4.0-1083.90
  18. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 4.15.0-192.203
  19. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.15.0-1140.151
  20. Upgrade

    Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1084.91~18.04.1
  21. Upgrade

    Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1150.165
  22. Upgrade

    Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1090.95~18.04.1
  23. Upgrade

    Upgrade ubuntu/linux-dell300x to a version that resolves this vulnerability.

    Fixed in 4.15.0-1052.57
  24. Upgrade

    Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1135.151
  25. Upgrade

    Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1087.95~18.04.1
  26. Upgrade

    Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-125.141~18.04.1
  27. Upgrade

    Upgrade ubuntu/linux-ibm-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1032.36~18.04.1
  28. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.15.0-1126.131
  29. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1105.116
  30. Upgrade

    Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1082.90~18.04.1
  31. Upgrade

    Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1069.79~18.04.1
  32. Upgrade

    Upgrade ubuntu/linux-raspi2 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1118.126
  33. Upgrade

    Upgrade ubuntu/linux-snapdragon to a version that resolves this vulnerability.

    Fixed in 4.15.0-1136.146
  34. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2079.84
  35. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2060.66
  36. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-1097.108
  37. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2044.49
  38. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 5.4.0-125.141
  39. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 5.4.0-1084.91
  40. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 5.4.0-1090.95
  41. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 5.4.0-1045.50
  42. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 5.4.0-1087.95
  43. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 5.4.0-1081.87
  44. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 5.4.0-1052.55
  45. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1032.36
  46. Upgrade

    Upgrade ubuntu/linux-iot to a version that resolves this vulnerability.

    Fixed in 5.4.0-1004.6
  47. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1074.79
  48. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 5.4.0-1082.90
  49. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 5.4.0-1069.79
  50. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1085.92+fips1
  51. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1090.95+fips1
  52. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1060.68
  53. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1087.95+fips1
  54. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch vt-drop-old-font-ioctls.patch

Event History

Jan 5, 2021
CVE Published
10:00 AM
Jul 18, 2022
CVE Published
via MITRE·02:44 PM
Data Sourced
via MITRE·02:44 PM
DescriptionWeakness
Data Sourced
via OSV·03:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-33656?

CVE-2021-33656 has a high severity rating due to the potential for memory corruption and denial of service when exploited.

2

How do I fix CVE-2021-33656?

To fix CVE-2021-33656, ensure that your kernel package is updated to a version that includes the patch, specifically at least 0:4.18.0-477.10.1.rt7.274.el8_8 for Red Hat or corresponding updates for other affected distributions.

3

Who is affected by CVE-2021-33656?

CVE-2021-33656 affects multiple Linux kernel versions, particularly those used in Red Hat and Huawei OpenEuler systems.

4

What can happen if CVE-2021-33656 is exploited?

Exploitation of CVE-2021-33656 could result in a kernel crash or the execution of arbitrary code leading to a system compromise.

5

How is CVE-2021-33656 triggered?

CVE-2021-33656 is triggered when a user with access to the console driver sends malicious data via the ioctl PIO_FONT command.

Company

Resources

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