UBUNTU-CVE-2021-47294: Medium severity ubuntu/linux-azure vulnerability

Q: Who is exposed to this issue?

Systems running one of the listed Ubuntu kernel packages are potentially exposed when the NET/ROM networking functionality is used. The issue affects socket lifetime handling after NET/ROM socket timers expire.

Q: What does an attacker need to exploit it?

The supplied severity vector indicates local access and low privileges are required, with no user interaction. The described impact is an unbalanced socket reference count that can prevent affected sockets from being freed, resulting in an availability impact.

Q: How can I tell whether a system is affected?

Check whether the system is running a listed Ubuntu kernel package and whether NET/ROM is enabled or used. The data does not provide affected or fixed package version numbers, so package status must be verified against the Ubuntu security advisory.

Published May 21, 2024

Updated

In the Linux kernel, the following vulnerability has been resolved: netrom: Decrease sock refcount when sock timers expire Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use sock timer API. It replaces modtimer() by skresettimer(), and deltimer() by skstoptimer(). Function skresettimer() will increase the refcount of sock if it is called on an inactive timer, hence, in case the timer expires, we need to decrease the refcount ourselves in the handler, otherwise, the sock refcount will be unbalanced and the sock will never be freed.

Affected Software

115 affected componentsFixes available

ubuntu/linux-azure<4.15.0-1124.137~14.04.1

4.15.0-1124.137~14.04.1

ubuntu/linux-aws<4.4.0-1149.155

4.4.0-1149.155

ubuntu/linux-lts-xenial<4.4.0-274.308~14.04.1

4.4.0-274.308~14.04.1

ubuntu/linux<4.4.0-274.308

4.4.0-274.308

ubuntu/linux-aws<4.4.0-1187.202

4.4.0-1187.202

ubuntu/linux-aws-hwe<4.15.0-1112.119~16.04.1

4.15.0-1112.119~16.04.1

ubuntu/linux-azure<4.15.0-1124.137~16.04.1

4.15.0-1124.137~16.04.1

ubuntu/linux-gcp<4.15.0-1109.123~16.04.1

4.15.0-1109.123~16.04.1

ubuntu/linux-hwe<4.15.0-159.167~16.04.1

4.15.0-159.167~16.04.1

ubuntu/linux-kvm<4.4.0-1150.161

4.4.0-1150.161

ubuntu/linux-oracle<4.15.0-1081.89~16.04.1

4.15.0-1081.89~16.04.1

ubuntu/linux-hwe-edge*

ubuntu/linux-fips<4.4.0-1119.126

4.4.0-1119.126

ubuntu/linux-fips*

ubuntu/linux<4.15.0-159.167

4.15.0-159.167

ubuntu/linux-aws<4.15.0-1112.119

4.15.0-1112.119

ubuntu/linux-aws-5.4<5.4.0-1057.60~18.04.1

5.4.0-1057.60~18.04.1

ubuntu/linux-azure-4.15<4.15.0-1124.137

4.15.0-1124.137

ubuntu/linux-azure-5.4<5.4.0-1059.62~18.04.1

5.4.0-1059.62~18.04.1

ubuntu/linux-gcp-4.15<4.15.0-1109.123

4.15.0-1109.123

ubuntu/linux-gcp-5.4<5.4.0-1053.57~18.04.1

5.4.0-1053.57~18.04.1

ubuntu/linux-hwe-5.4<5.4.0-87.98~18.04.1

5.4.0-87.98~18.04.1

ubuntu/linux-kvm<4.15.0-1100.102

4.15.0-1100.102

ubuntu/linux-oracle<4.15.0-1081.89

4.15.0-1081.89

ubuntu/linux-oracle-5.4<5.4.0-1055.59~18.04.1

5.4.0-1055.59~18.04.1

ubuntu/linux-raspi-5.4<5.4.0-1044.48~18.04.1

5.4.0-1044.48~18.04.1

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<4.15.0-2054.56

4.15.0-2054.56

ubuntu/linux-azure-fips<4.15.0-2036.40

4.15.0-2036.40

ubuntu/linux-fips<4.15.0-1070.79

4.15.0-1070.79

ubuntu/linux-gcp-fips<4.15.0-2019.21

4.15.0-2019.21

ubuntu/linux-fips*

ubuntu/linux<5.4.0-88.99

5.4.0-88.99

ubuntu/linux-aws<5.4.0-1057.60

5.4.0-1057.60

ubuntu/linux-azure<5.4.0-1059.62

5.4.0-1059.62

ubuntu/linux-bluefield<5.4.0-1019.22

5.4.0-1019.22

ubuntu/linux-gcp<5.4.0-1053.57

5.4.0-1053.57

ubuntu/linux-gkeop<5.4.0-1024.25

5.4.0-1024.25

ubuntu/linux-ibm<5.4.0-1005.6

5.4.0-1005.6

ubuntu/linux-kvm<5.4.0-1047.49

5.4.0-1047.49

ubuntu/linux-oracle<5.4.0-1055.59

5.4.0-1055.59

ubuntu/linux-raspi<5.4.0-1044.48

5.4.0-1044.48

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-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

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<5.4.0-1069.73+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<5.4.0-1034.40

5.4.0-1034.40

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-allwinner-5.19*

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-nvidia-6.2*

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-raspi-realtime*

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1124.137~14.04.1
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.4.0-1149.155
Upgrade
Upgrade ubuntu/linux-lts-xenial to a version that resolves this vulnerability.
Fixed in 4.4.0-274.308~14.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 4.4.0-274.308
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.4.0-1187.202
Upgrade
Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-1112.119~16.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1124.137~16.04.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 4.15.0-1109.123~16.04.1
Upgrade
Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-159.167~16.04.1
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 4.4.0-1150.161
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1081.89~16.04.1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 4.4.0-1119.126
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 4.15.0-159.167
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.15.0-1112.119
Upgrade
Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1057.60~18.04.1
Upgrade
Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1124.137
Upgrade
Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1059.62~18.04.1
Upgrade
Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1109.123
Upgrade
Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1053.57~18.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-87.98~18.04.1
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 4.15.0-1100.102
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1081.89
Upgrade
Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1055.59~18.04.1
Upgrade
Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1044.48~18.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2054.56
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2036.40
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-1070.79
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2019.21
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.4.0-88.99
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.4.0-1057.60
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.4.0-1059.62
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.4.0-1019.22
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.4.0-1053.57
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.4.0-1024.25
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.4.0-1005.6
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.4.0-1047.49
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.4.0-1055.59
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.4.0-1044.48
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1069.73+fips2
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1073.76+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1034.40
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1067.71~20.04.1
Upgrade
Upgrade Linux kernel netrom to a version that resolves this vulnerability.
Patch 63346650c1a9

Event History

May 21, 2024

CVE Published

via OSV·03:15 PM

Data Sourced

via OSV·03:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Who is exposed to this issue?

Systems running one of the listed Ubuntu kernel packages are potentially exposed when the NET/ROM networking functionality is used. The issue affects socket lifetime handling after NET/ROM socket timers expire.

What does an attacker need to exploit it?

The supplied severity vector indicates local access and low privileges are required, with no user interaction. The described impact is an unbalanced socket reference count that can prevent affected sockets from being freed, resulting in an availability impact.

How can I tell whether a system is affected?

Check whether the system is running a listed Ubuntu kernel package and whether NET/ROM is enabled or used. The data does not provide affected or fixed package version numbers, so package status must be verified against the Ubuntu security advisory.

UBUNTU-CVE-2021-47294: Medium severity ubuntu/linux-azure vulnerability

Affected Software

Remediation

Event History

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

How can I tell whether a system is affected?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

How can I tell whether a system is affected?