UBUNTU-CVE-2021-3640: Use After Free

Published Jul 18, 2021
·
Updated

A flaw use-after-free in function scosocksendmsg() of the Linux kernel HCI subsystem was found in the way user calls ioct UFFDIOREGISTER or other way triggers race condition of the call scoconndel() together with the call scosocksendmsg() with the expected controllable faulting memory page. A privileged local user could use this flaw to crash the system or escalate their privileges on the system.

Affected Software

100 affected componentsFixes available
ubuntu/linux-azure<4.15.0-1130.143~14.04.1
4.15.0-1130.143~14.04.1
ubuntu/linux<3.13.0-219.270
3.13.0-219.270
ubuntu/linux-aws<4.4.0-1161.167
4.4.0-1161.167
ubuntu/linux-lts-xenial<4.4.0-290.324~14.04.1
4.4.0-290.324~14.04.1
ubuntu/linux-aws-hwe<4.15.0-1119.126~16.04.2
4.15.0-1119.126~16.04.2
ubuntu/linux-azure<4.15.0-1130.143~16.04.1
4.15.0-1130.143~16.04.1
ubuntu/linux-gcp<4.15.0-1115.129~16.04.1
4.15.0-1115.129~16.04.1
ubuntu/linux-hwe<4.15.0-167.175~16.04.1
4.15.0-167.175~16.04.1
ubuntu/linux-oracle<4.15.0-1086.94~16.04.1
4.15.0-1086.94~16.04.1
ubuntu/linux<4.4.0-290.324
4.4.0-290.324
ubuntu/linux-hwe-edge*
ubuntu/linux-kvm<4.4.0-1162.173
4.4.0-1162.173
ubuntu/linux-fips<4.4.0-1131.138
4.4.0-1131.138
ubuntu/linux-fips*
ubuntu/linux<4.15.0-167.175
4.15.0-167.175
ubuntu/linux-aws<4.15.0-1119.127
4.15.0-1119.127
ubuntu/linux-aws-5.4<5.4.0-1064.67~18.04.1
5.4.0-1064.67~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1131.144
4.15.0-1131.144
ubuntu/linux-azure-5.4<5.4.0-1068.71~18.04.1
5.4.0-1068.71~18.04.1
ubuntu/linux-dell300x<4.15.0-1034.39
4.15.0-1034.39
ubuntu/linux-gcp-4.15<4.15.0-1115.129
4.15.0-1115.129
ubuntu/linux-gcp-5.4<5.4.0-1063.67~18.04.1
5.4.0-1063.67~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1061.64~18.04.1
5.4.0-1061.64~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1032.33~18.04.1
5.4.0-1032.33~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-97.110~18.04.1
5.4.0-97.110~18.04.1
ubuntu/linux-ibm-5.4<5.4.0-1014.15~18.04.1
5.4.0-1014.15~18.04.1
ubuntu/linux-kvm<4.15.0-1106.108
4.15.0-1106.108
ubuntu/linux-oracle<4.15.0-1086.94
4.15.0-1086.94
ubuntu/linux-oracle-5.4<5.4.0-1062.66~18.04.1
5.4.0-1062.66~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1052.58~18.04.1
5.4.0-1052.58~18.04.1
ubuntu/linux-raspi2<4.15.0-1102.109
4.15.0-1102.109
ubuntu/linux-snapdragon<4.15.0-1119.128
4.15.0-1119.128
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-gke-4.15*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2060.62
4.15.0-2060.62
ubuntu/linux-azure-fips<4.15.0-2042.46
4.15.0-2042.46
ubuntu/linux-fips<4.15.0-1076.85
4.15.0-1076.85
ubuntu/linux-gcp-fips<4.15.0-2025.27
4.15.0-2025.27
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-97.110
5.4.0-97.110
ubuntu/linux-aws<5.4.0-1064.67
5.4.0-1064.67
ubuntu/linux-aws-5.11<5.11.0-1028.31~20.04.1
5.11.0-1028.31~20.04.1
ubuntu/linux-aws-5.13<5.13.0-1012.13~20.04.1
5.13.0-1012.13~20.04.1
ubuntu/linux-azure<5.4.0-1068.71
5.4.0-1068.71
ubuntu/linux-azure-5.11<5.11.0-1028.31~20.04.2
5.11.0-1028.31~20.04.2
ubuntu/linux-azure-5.13<5.13.0-1013.15~20.04.1
5.13.0-1013.15~20.04.1
ubuntu/linux-bluefield<5.4.0-1026.29
5.4.0-1026.29
ubuntu/linux-gcp<5.4.0-1063.67
5.4.0-1063.67
ubuntu/linux-gcp-5.11<5.11.0-1029.33~20.04.3
5.11.0-1029.33~20.04.3
ubuntu/linux-gcp-5.13<5.13.0-1013.16~20.04.1
5.13.0-1013.16~20.04.1
ubuntu/linux-gke<5.4.0-1061.64
5.4.0-1061.64
ubuntu/linux-gkeop<5.4.0-1032.33
5.4.0-1032.33
ubuntu/linux-hwe-5.13<5.13.0-28.31~20.04.1
5.13.0-28.31~20.04.1
ubuntu/linux-ibm<5.4.0-1013.14
5.4.0-1013.14
ubuntu/linux-kvm<5.4.0-1054.56
5.4.0-1054.56
ubuntu/linux-oem-5.10<5.10.0-1053.55
5.10.0-1053.55
ubuntu/linux-oem-5.13<5.13.0-1029.36
5.13.0-1029.36
ubuntu/linux-oem-5.14<5.14.0-1013.13
5.14.0-1013.13
ubuntu/linux-oracle<5.4.0-1062.66
5.4.0-1062.66
ubuntu/linux-oracle-5.11<5.11.0-1028.31~20.04.1
5.11.0-1028.31~20.04.1
ubuntu/linux-oracle-5.13<5.13.0-1016.20~20.04.1
5.13.0-1016.20~20.04.1
ubuntu/linux-raspi<5.4.0-1052.58
5.4.0-1052.58
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.8*
ubuntu/linux-gcp-5.8*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.8*
ubuntu/linux-intel-5.13*
ubuntu/linux-oem-5.6*
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<5.4.0-1069.73+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-fips<5.4.0-1041.47
5.4.0-1041.47
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-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 ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1130.143~14.04.1
  2. Upgrade

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

    Fixed in 3.13.0-219.270
  3. Upgrade

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

    Fixed in 4.4.0-1161.167
  4. Upgrade

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

    Fixed in 4.4.0-290.324~14.04.1
  5. Upgrade

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

    Fixed in 4.15.0-1119.126~16.04.2
  6. Upgrade

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

    Fixed in 4.15.0-1130.143~16.04.1
  7. Upgrade

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

    Fixed in 4.15.0-1115.129~16.04.1
  8. Upgrade

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

    Fixed in 4.15.0-167.175~16.04.1
  9. Upgrade

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

    Fixed in 4.15.0-1086.94~16.04.1
  10. Upgrade

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

    Fixed in 4.4.0-290.324
  11. Upgrade

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

    Fixed in 4.4.0-1162.173
  12. Upgrade

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

    Fixed in 4.4.0-1131.138
  13. Upgrade

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

    Fixed in 4.15.0-167.175
  14. Upgrade

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

    Fixed in 4.15.0-1119.127
  15. Upgrade

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

    Fixed in 5.4.0-1064.67~18.04.1
  16. Upgrade

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

    Fixed in 4.15.0-1131.144
  17. Upgrade

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

    Fixed in 5.4.0-1068.71~18.04.1
  18. Upgrade

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

    Fixed in 4.15.0-1034.39
  19. Upgrade

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

    Fixed in 4.15.0-1115.129
  20. Upgrade

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

    Fixed in 5.4.0-1063.67~18.04.1
  21. Upgrade

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

    Fixed in 5.4.0-1061.64~18.04.1
  22. Upgrade

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

    Fixed in 5.4.0-1032.33~18.04.1
  23. Upgrade

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

    Fixed in 5.4.0-97.110~18.04.1
  24. Upgrade

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

    Fixed in 5.4.0-1014.15~18.04.1
  25. Upgrade

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

    Fixed in 4.15.0-1106.108
  26. Upgrade

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

    Fixed in 4.15.0-1086.94
  27. Upgrade

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

    Fixed in 5.4.0-1062.66~18.04.1
  28. Upgrade

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

    Fixed in 5.4.0-1052.58~18.04.1
  29. Upgrade

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

    Fixed in 4.15.0-1102.109
  30. Upgrade

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

    Fixed in 4.15.0-1119.128
  31. Upgrade

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

    Fixed in 4.15.0-2060.62
  32. Upgrade

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

    Fixed in 4.15.0-2042.46
  33. Upgrade

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

    Fixed in 4.15.0-1076.85
  34. Upgrade

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

    Fixed in 4.15.0-2025.27
  35. Upgrade

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

    Fixed in 5.4.0-97.110
  36. Upgrade

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

    Fixed in 5.4.0-1064.67
  37. Upgrade

    Upgrade ubuntu/linux-aws-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1028.31~20.04.1
  38. Upgrade

    Upgrade ubuntu/linux-aws-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1012.13~20.04.1
  39. Upgrade

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

    Fixed in 5.4.0-1068.71
  40. Upgrade

    Upgrade ubuntu/linux-azure-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1028.31~20.04.2
  41. Upgrade

    Upgrade ubuntu/linux-azure-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1013.15~20.04.1
  42. Upgrade

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

    Fixed in 5.4.0-1026.29
  43. Upgrade

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

    Fixed in 5.4.0-1063.67
  44. Upgrade

    Upgrade ubuntu/linux-gcp-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1029.33~20.04.3
  45. Upgrade

    Upgrade ubuntu/linux-gcp-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1013.16~20.04.1
  46. Upgrade

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

    Fixed in 5.4.0-1061.64
  47. Upgrade

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

    Fixed in 5.4.0-1032.33
  48. Upgrade

    Upgrade ubuntu/linux-hwe-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-28.31~20.04.1
  49. Upgrade

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

    Fixed in 5.4.0-1013.14
  50. Upgrade

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

    Fixed in 5.4.0-1054.56
  51. Upgrade

    Upgrade ubuntu/linux-oem-5.10 to a version that resolves this vulnerability.

    Fixed in 5.10.0-1053.55
  52. Upgrade

    Upgrade ubuntu/linux-oem-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1029.36
  53. Upgrade

    Upgrade ubuntu/linux-oem-5.14 to a version that resolves this vulnerability.

    Fixed in 5.14.0-1013.13
  54. Upgrade

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

    Fixed in 5.4.0-1062.66
  55. Upgrade

    Upgrade ubuntu/linux-oracle-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1028.31~20.04.1
  56. Upgrade

    Upgrade ubuntu/linux-oracle-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1016.20~20.04.1
  57. Upgrade

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

    Fixed in 5.4.0-1052.58
  58. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  59. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  60. Upgrade

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

    Fixed in 5.4.0-1041.47
  61. 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

Jul 18, 2021
CVE Published
via OSV·12:00 PM
Data Sourced
via OSV·12:00 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

Which Ubuntu kernel packages are listed as affected?

The listed packages are ubuntu/linux, ubuntu/linux-azure, ubuntu/linux-aws, ubuntu/linux-gcp, and their FIPS variants: ubuntu/linux-fips, ubuntu/linux-azure-fips, ubuntu/linux-aws-fips, and ubuntu/linux-gcp-fips.

2

What level of access does an attacker need to exploit this issue?

Exploitation requires privileged local access. The attacker must be able to trigger a race between sco_conn_del() and sco_sock_sendmsg(), including use of UFFDIO_REGISTER or another method that creates the race with a controllable faulting memory page.

Company

Resources

Contact

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