CVE-2020-25668: Race Condition

Published May 26, 2021
·
Updated

A flaw was found in Linux Kernel because access to the global variable fgconsole is not properly synchronized leading to a use after free in confontop.

Other sources

In vtdisallocate and related functions of vtioctl.c, there is a possible out of bounds write due to a use after free. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.

— OSV

Affected Software

132 affected componentsFixes available
Linux Linux kernel<4.4.242
Linux Linux kernel>=4.5<4.9.242
Linux Linux kernel>=4.10<4.14.204
Linux Linux kernel>=4.15<4.19.155
Linux Linux kernel>=4.20<5.4.75
Linux Linux kernel>=5.5<5.9.5
Debian Debian Linux=9.0
NetApp Cloud Backup
NetApp Solidfire \& Hci Management Node
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
NetApp H410c Firmware
NetApp H410c
NetApp H300s Firmware
NetApp H300s
NetApp H500s Firmware
NetApp H500s
NetApp H700s Firmware
NetApp H700s
NetApp H300e Firmware
NetApp H300e
NetApp H500e Firmware
NetApp H500e
NetApp H700e Firmware
NetApp H700e
NetApp H410s Firmware
NetApp H410s
NetApp A250 Firmware
NetApp A250
NetApp 500f Firmware
NetApp 500f
All of the following
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
All of the following
NetApp H410c Firmware
NetApp H410c
All of the following
NetApp H300s Firmware
NetApp H300s
All of the following
NetApp H500s Firmware
NetApp H500s
All of the following
NetApp H700s Firmware
NetApp H700s
All of the following
NetApp H300e Firmware
NetApp H300e
All of the following
NetApp H500e Firmware
NetApp H500e
All of the following
NetApp H700e Firmware
NetApp H700e
All of the following
NetApp H410s Firmware
NetApp H410s
All of the following
NetApp A250 Firmware
NetApp A250
All of the following
NetApp 500f Firmware
NetApp 500f
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1
android/:linux_kernel:>=:0<:2021-12-05
:2021-12-05
ubuntu/linux-aws<4.4.0-1083.87
4.4.0-1083.87
ubuntu/linux-azure<4.15.0-1103.114~14.04.1
4.15.0-1103.114~14.04.1
ubuntu/linux-lts-xenial<4.4.0-198.230~14.04.1
4.4.0-198.230~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-198.230
4.4.0-198.230
ubuntu/linux-aws<4.4.0-1119.133
4.4.0-1119.133
ubuntu/linux-aws-hwe<4.15.0-1091.96~16.04.1
4.15.0-1091.96~16.04.1
ubuntu/linux-azure<4.15.0-1103.114~16.04.1
4.15.0-1103.114~16.04.1
ubuntu/linux-gcp<4.15.0-1091.104~16.04.1
4.15.0-1091.104~16.04.1
ubuntu/linux-hwe<4.15.0-129.132~16.04.1
4.15.0-129.132~16.04.1
ubuntu/linux-kvm<4.4.0-1085.94
4.4.0-1085.94
ubuntu/linux-oracle<4.15.0-1062.68~16.04.1
4.15.0-1062.68~16.04.1
ubuntu/linux-raspi2<4.4.0-1143.153
4.4.0-1143.153
ubuntu/linux-snapdragon<4.4.0-1147.157
4.4.0-1147.157
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1052.58
4.4.0-1052.58
ubuntu/linux-fips*
ubuntu/linux<4.15.0-129.132
4.15.0-129.132
ubuntu/linux-aws<4.15.0-1091.96
4.15.0-1091.96
ubuntu/linux-aws-5.4<5.4.0-1034.35~18.04.1
5.4.0-1034.35~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1103.114
4.15.0-1103.114
ubuntu/linux-azure-5.4<5.4.0-1035.36~18.04.1
5.4.0-1035.36~18.04.1
ubuntu/linux-dell300x<4.15.0-1010.14
4.15.0-1010.14
ubuntu/linux-gcp-4.15<4.15.0-1091.104
4.15.0-1091.104
ubuntu/linux-gcp-5.4<5.4.0-1033.35~18.04.1
5.4.0-1033.35~18.04.1
ubuntu/linux-gke-4.15<4.15.0-1077.82
4.15.0-1077.82
ubuntu/linux-gke-5.4<5.4.0-1033.35~18.04.1
5.4.0-1033.35~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1008.9~18.04.1
5.4.0-1008.9~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-59.65~18.04.1
5.4.0-59.65~18.04.1
ubuntu/linux-kvm<4.15.0-1082.84
4.15.0-1082.84
ubuntu/linux-oracle<4.15.0-1062.68
4.15.0-1062.68
ubuntu/linux-oracle-5.4<5.4.0-1034.36~18.04.1
5.4.0-1034.36~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1026.29~18.04.1
5.4.0-1026.29~18.04.1
ubuntu/linux-raspi2<4.15.0-1077.82
4.15.0-1077.82
ubuntu/linux-snapdragon<4.15.0-1094.103
4.15.0-1094.103
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-gcp-edge*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2034.35
4.15.0-2034.35
ubuntu/linux-azure-fips<4.15.0-2016.18
4.15.0-2016.18
ubuntu/linux-fips<4.15.0-1049.56
4.15.0-1049.56
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-59.65
5.4.0-59.65
ubuntu/linux-aws<5.4.0-1034.35
5.4.0-1034.35
ubuntu/linux-azure<5.4.0-1035.36
5.4.0-1035.36
ubuntu/linux-gcp<5.4.0-1033.35
5.4.0-1033.35
ubuntu/linux-hwe-5.8<5.8.0-44.50~20.04.1
5.8.0-44.50~20.04.1
ubuntu/linux-kvm<5.4.0-1031.32
5.4.0-1031.32
ubuntu/linux-oem-5.6<5.6.0-1050.54
5.6.0-1050.54
ubuntu/linux-oracle<5.4.0-1034.36
5.4.0-1034.36
ubuntu/linux-raspi<5.4.0-1026.29
5.4.0-1026.29
ubuntu/linux-riscv<5.4.0-40.45
5.4.0-40.45
ubuntu/linux-riscv-5.8<5.8.0-17.19~20.04.1
5.8.0-17.19~20.04.1
ubuntu/linux-azure-fde-5.15<5.15.0-1114.123~20.04.1
5.15.0-1114.123~20.04.1
ubuntu/linux-raspi2*
ubuntu/linux-aws-fips<5.4.0-1069.73+fips2
5.4.0-1069.73+fips2
ubuntu/linux-azure-fips<5.4.0-1073.76+fips1
5.4.0-1073.76+fips1
ubuntu/linux-gcp-fips<5.4.0-1067.71~20.04.1
5.4.0-1067.71~20.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-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 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
  2. Upgrade

    Upgrade android/:linux_kernel: to a version that resolves this vulnerability.

    Fixed in :2021-12-05
  3. Upgrade

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

    Fixed in 4.4.0-1083.87
  4. Upgrade

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

    Fixed in 4.15.0-1103.114~14.04.1
  5. Upgrade

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

    Fixed in 4.4.0-198.230~14.04.1
  6. Upgrade

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

    Fixed in 4.4.0-198.230
  7. Upgrade

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

    Fixed in 4.4.0-1119.133
  8. Upgrade

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

    Fixed in 4.15.0-1091.96~16.04.1
  9. Upgrade

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

    Fixed in 4.15.0-1103.114~16.04.1
  10. Upgrade

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

    Fixed in 4.15.0-1091.104~16.04.1
  11. Upgrade

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

    Fixed in 4.15.0-129.132~16.04.1
  12. Upgrade

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

    Fixed in 4.4.0-1085.94
  13. Upgrade

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

    Fixed in 4.15.0-1062.68~16.04.1
  14. Upgrade

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

    Fixed in 4.4.0-1143.153
  15. Upgrade

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

    Fixed in 4.4.0-1147.157
  16. Upgrade

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

    Fixed in 4.4.0-1052.58
  17. Upgrade

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

    Fixed in 4.15.0-129.132
  18. Upgrade

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

    Fixed in 4.15.0-1091.96
  19. Upgrade

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

    Fixed in 5.4.0-1034.35~18.04.1
  20. Upgrade

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

    Fixed in 4.15.0-1103.114
  21. Upgrade

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

    Fixed in 5.4.0-1035.36~18.04.1
  22. Upgrade

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

    Fixed in 4.15.0-1010.14
  23. Upgrade

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

    Fixed in 4.15.0-1091.104
  24. Upgrade

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

    Fixed in 5.4.0-1033.35~18.04.1
  25. Upgrade

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

    Fixed in 4.15.0-1077.82
  26. Upgrade

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

    Fixed in 5.4.0-1033.35~18.04.1
  27. Upgrade

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

    Fixed in 5.4.0-1008.9~18.04.1
  28. Upgrade

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

    Fixed in 5.4.0-59.65~18.04.1
  29. Upgrade

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

    Fixed in 4.15.0-1082.84
  30. Upgrade

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

    Fixed in 4.15.0-1062.68
  31. Upgrade

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

    Fixed in 5.4.0-1034.36~18.04.1
  32. Upgrade

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

    Fixed in 5.4.0-1026.29~18.04.1
  33. Upgrade

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

    Fixed in 4.15.0-1077.82
  34. Upgrade

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

    Fixed in 4.15.0-1094.103
  35. Upgrade

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

    Fixed in 4.15.0-2034.35
  36. Upgrade

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

    Fixed in 4.15.0-2016.18
  37. Upgrade

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

    Fixed in 4.15.0-1049.56
  38. Upgrade

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

    Fixed in 5.4.0-59.65
  39. Upgrade

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

    Fixed in 5.4.0-1034.35
  40. Upgrade

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

    Fixed in 5.4.0-1035.36
  41. Upgrade

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

    Fixed in 5.4.0-1033.35
  42. Upgrade

    Upgrade ubuntu/linux-hwe-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-44.50~20.04.1
  43. Upgrade

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

    Fixed in 5.4.0-1031.32
  44. Upgrade

    Upgrade ubuntu/linux-oem-5.6 to a version that resolves this vulnerability.

    Fixed in 5.6.0-1050.54
  45. Upgrade

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

    Fixed in 5.4.0-1034.36
  46. Upgrade

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

    Fixed in 5.4.0-1026.29
  47. Upgrade

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

    Fixed in 5.4.0-40.45
  48. Upgrade

    Upgrade ubuntu/linux-riscv-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-17.19~20.04.1
  49. Upgrade

    Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1114.123~20.04.1
  50. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  51. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  52. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1

Event History

Nov 2, 2020
CVE Published
via OSV·12:00 AM
Data Sourced
via OSV·12:00 AM
DescriptionSeverityAffected Software
May 26, 2021
CVE Published
via MITRE·11:11 AM
Data Sourced
via MITRE·11:11 AM
DescriptionWeakness
Dec 1, 2021
Advisory Published
via OSV·12:00 AM

Frequently Asked Questions

1

What is the severity of CVE-2020-25668?

CVE-2020-25668 has been classified as a medium severity vulnerability in the Linux Kernel.

2

How do I fix CVE-2020-25668?

To fix CVE-2020-25668, update the Linux Kernel to version 5.10.223-1 or later.

3

Which versions of the Linux Kernel are affected by CVE-2020-25668?

CVE-2020-25668 affects Linux Kernel versions up to 4.4.242 and several versions between 4.5 and 5.9.5.

4

What type of vulnerability is CVE-2020-25668?

CVE-2020-25668 is a use-after-free vulnerability that occurs due to improper synchronization.

5

Is there an exploit available for CVE-2020-25668?

While there may not be widely reported exploits specifically targeting CVE-2020-25668, the vulnerability poses a risk that could be leveraged by attackers.

Company

Resources

Contact

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