CVE-2019-19227: Null Pointer Dereference

Published Nov 22, 2019
·
Updated

In the AppleTalk subsystem in the Linux kernel before 5.1, there is a potential NULL pointer dereference because registersnapclient may return NULL. This will lead to denial of service in net/appletalk/aarp.c and net/appletalk/ddp.c, as demonstrated by unregistersnapclient, aka CID-9804501fa122.

Affected Software

50 affected componentsFixes available
Linux Linux kernel<5.1
debian/linux
6.1.176-16.1.190-16.12.107-16.12.113-17.2.12-17.2.13-1
ubuntu/linux-aws<4.4.0-1061.65
4.4.0-1061.65
ubuntu/linux-azure<4.15.0-1071.76~14.04.1
4.15.0-1071.76~14.04.1
ubuntu/linux-lts-xenial<4.4.0-173.203~14.04.1
4.4.0-173.203~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-173.203
4.4.0-173.203
ubuntu/linux-aws<4.4.0-1101.112
4.4.0-1101.112
ubuntu/linux-aws-hwe<4.15.0-1060.62~16.04.1
4.15.0-1060.62~16.04.1
ubuntu/linux-azure<4.15.0-1071.76
4.15.0-1071.76
ubuntu/linux-gcp<4.15.0-1055.59
4.15.0-1055.59
ubuntu/linux-hwe<4.15.0-88.88~16.04.1
4.15.0-88.88~16.04.1
ubuntu/linux-kvm<4.4.0-1065.72
4.4.0-1065.72
ubuntu/linux-oracle<4.15.0-1033.36~16.04.1
4.15.0-1033.36~16.04.1
ubuntu/linux-raspi2<4.4.0-1128.137
4.4.0-1128.137
ubuntu/linux-snapdragon<4.4.0-1132.140
4.4.0-1132.140
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1028.33
4.4.0-1028.33
ubuntu/linux-fips*
ubuntu/linux<4.15.0-88.88
4.15.0-88.88
ubuntu/linux-aws<4.15.0-1060.62
4.15.0-1060.62
ubuntu/linux-aws-5.0<5.0.0-1024.27~18.04.1
5.0.0-1024.27~18.04.1
ubuntu/linux-azure<5.0.0-1029.31~18.04.1
5.0.0-1029.31~18.04.1
ubuntu/linux-gcp<5.0.0-1029.30~18.04.1
5.0.0-1029.30~18.04.1
ubuntu/linux-gke-4.15<4.15.0-1052.55
4.15.0-1052.55
ubuntu/linux-gke-5.0<5.0.0-1029.30~18.04.1
5.0.0-1029.30~18.04.1
ubuntu/linux-hwe<5.3.0-26.28~18.04.1
5.3.0-26.28~18.04.1
ubuntu/linux-kvm<4.15.0-1053.53
4.15.0-1053.53
ubuntu/linux-oem<4.15.0-1073.83
4.15.0-1073.83
ubuntu/linux-oem-osp1<5.0.0-1037.42
5.0.0-1037.42
ubuntu/linux-oracle<4.15.0-1033.36
4.15.0-1033.36
ubuntu/linux-oracle-5.0<5.0.0-1010.15~18.04.1
5.0.0-1010.15~18.04.1
ubuntu/linux-raspi2<4.15.0-1055.59
4.15.0-1055.59
ubuntu/linux-snapdragon<4.15.0-1072.79
4.15.0-1072.79
ubuntu/linux-azure-edge*
ubuntu/linux-gcp-edge*
ubuntu/linux-hwe-edge*
ubuntu/linux-aws-fips<4.15.0-2018.18
4.15.0-2018.18
ubuntu/linux-azure-fips<4.15.0-2006.7
4.15.0-2006.7
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-azure-fde*
ubuntu/linux-gke*
ubuntu/linux-riscv*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-raspi-realtime*
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1
  2. Upgrade

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

    Fixed in 4.4.0-1061.65
  3. Upgrade

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

    Fixed in 4.15.0-1071.76~14.04.1
  4. Upgrade

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

    Fixed in 4.4.0-173.203~14.04.1
  5. Upgrade

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

    Fixed in 4.4.0-173.203
  6. Upgrade

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

    Fixed in 4.4.0-1101.112
  7. Upgrade

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

    Fixed in 4.15.0-1060.62~16.04.1
  8. Upgrade

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

    Fixed in 4.15.0-1071.76
  9. Upgrade

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

    Fixed in 4.15.0-1055.59
  10. Upgrade

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

    Fixed in 4.15.0-88.88~16.04.1
  11. Upgrade

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

    Fixed in 4.4.0-1065.72
  12. Upgrade

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

    Fixed in 4.15.0-1033.36~16.04.1
  13. Upgrade

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

    Fixed in 4.4.0-1128.137
  14. Upgrade

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

    Fixed in 4.4.0-1132.140
  15. Upgrade

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

    Fixed in 4.4.0-1028.33
  16. Upgrade

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

    Fixed in 4.15.0-88.88
  17. Upgrade

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

    Fixed in 4.15.0-1060.62
  18. Upgrade

    Upgrade ubuntu/linux-aws-5.0 to a version that resolves this vulnerability.

    Fixed in 5.0.0-1024.27~18.04.1
  19. Upgrade

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

    Fixed in 5.0.0-1029.31~18.04.1
  20. Upgrade

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

    Fixed in 5.0.0-1029.30~18.04.1
  21. Upgrade

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

    Fixed in 4.15.0-1052.55
  22. Upgrade

    Upgrade ubuntu/linux-gke-5.0 to a version that resolves this vulnerability.

    Fixed in 5.0.0-1029.30~18.04.1
  23. Upgrade

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

    Fixed in 5.3.0-26.28~18.04.1
  24. Upgrade

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

    Fixed in 4.15.0-1053.53
  25. Upgrade

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

    Fixed in 4.15.0-1073.83
  26. Upgrade

    Upgrade ubuntu/linux-oem-osp1 to a version that resolves this vulnerability.

    Fixed in 5.0.0-1037.42
  27. Upgrade

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

    Fixed in 4.15.0-1033.36
  28. Upgrade

    Upgrade ubuntu/linux-oracle-5.0 to a version that resolves this vulnerability.

    Fixed in 5.0.0-1010.15~18.04.1
  29. Upgrade

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

    Fixed in 4.15.0-1055.59
  30. Upgrade

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

    Fixed in 4.15.0-1072.79
  31. Upgrade

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

    Fixed in 4.15.0-2018.18
  32. Upgrade

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

    Fixed in 4.15.0-2006.7

Event History

Nov 22, 2019
CVE Published
via Ubuntu·12:00 AM
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
CVE Published
via MITRE·01:39 PM
Data Sourced
via MITRE·01:39 PM
Description
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityWeaknessAffected Software

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2019-19227?

CVE-2019-19227 has a medium severity level due to its potential to cause denial of service.

2

How do I fix CVE-2019-19227?

To fix CVE-2019-19227, you should upgrade to the Linux kernel version 5.1 or later.

3

Which versions of the Linux kernel are affected by CVE-2019-19227?

CVE-2019-19227 affects the Linux kernel versions prior to 5.1.

4

What components are impacted by CVE-2019-19227?

CVE-2019-19227 impacts the AppleTalk subsystem, specifically in the files net/appletalk/aarp.c and net/appletalk/ddp.c.

5

What kind of attack does CVE-2019-19227 enable?

CVE-2019-19227 enables denial of service attacks due to a potential NULL pointer dereference.

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