UBUNTU-CVE-2024-49960: Use After Free

Q: What conditions are required to trigger the use-after-free?

An ext4 filesystem mount must fail, and the failed-mount path must encounter a read I/O error while ext4_stop_mmpd is called. That error can re-arm the filesystem error-reporting timer after the normal timer-cancellation step.

Q: Is this remotely exploitable without access to the affected system?

The supplied CVSS vector rates attack vector as local and privileges required as low. Exploitation therefore requires local access with low privileges rather than unauthenticated remote access.

Q: What is the consequence of the vulnerable cleanup path?

The ext4 error-reporting timer can remain active after the ext4 superblock information is freed, causing a timer use-after-free. The provided severity vector indicates potential high impact to confidentiality, integrity, and availability.

Q: Which Ubuntu kernel packages are identified as affected?

The listed software includes ubuntu/linux-realtime, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-gke, ubuntu/linux-gkeop, ubuntu/linux-riscv, ubuntu/linux-fips, and ubuntu/linux-hwe-edge.

Published Oct 21, 2024

Updated

In the Linux kernel, the following vulnerability has been resolved: ext4: fix timer use-after-free on failed mount Syzbot has found an ODEBUG bug in ext4fillsuper The deltimersync function cancels the serrreport timer, which reminds about filesystem errors daily. We should guarantee the timer is no longer active before kfree(sbi). When filesystem mounting fails, the flow goes to failedmount3, where an error occurs when ext4stopmmpd is called, causing a read I/O failure. This triggers the ext4handleerror function that ultimately re-arms the timer, leaving the serrreport timer active before kfree(sbi) is called. Fix the issue by canceling the serrreport timer after calling ext4stopmmpd.

Affected Software

149 affected componentsFixes available

ubuntu/linux-hwe-edge*

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-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.15<5.15.0-1088.95~20.04.1

5.15.0-1088.95~20.04.1

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.15<5.15.0-1094.103~20.04.1

5.15.0-1094.103~20.04.1

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde*

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.15<5.15.0-1087.96~20.04.2

5.15.0-1087.96~20.04.2

ubuntu/linux-gcp-5.8*

ubuntu/linux-gke*

ubuntu/linux-gke-5.15*

ubuntu/linux-gkeop*

ubuntu/linux-gkeop-5.15*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.15<5.15.0-144.157~20.04.1

5.15.0-144.157~20.04.1

ubuntu/linux-hwe-5.8*

ubuntu/linux-ibm-5.15<5.15.0-1080.83~20.04.1

5.15.0-1080.83~20.04.1

ubuntu/linux-intel-5.13*

ubuntu/linux-intel-iotg-5.15<5.15.0-1083.89~20.04.1

5.15.0-1083.89~20.04.1

ubuntu/linux-lowlatency-hwe-5.15<5.15.0-144.157~20.04.1

5.15.0-144.157~20.04.1

ubuntu/linux-nvidia-tegra-5.15<5.15.0-1041.41~20.04.1

5.15.0-1041.41~20.04.1

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-5.15<5.15.0-1085.91~20.04.3

5.15.0-1085.91~20.04.3

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.15<5.15.0-1083.87~20.04.1

5.15.0-1083.87~20.04.1

ubuntu/linux-riscv-5.8*

ubuntu/linux<5.15.0-144.157

5.15.0-144.157

ubuntu/linux-allwinner-5.19*

ubuntu/linux-aws<5.15.0-1088.95

5.15.0-1088.95

ubuntu/linux-aws-5.19*

ubuntu/linux-aws-6.2*

ubuntu/linux-aws-6.5*

ubuntu/linux-aws-6.8<6.8.0-1023.25~22.04.1

6.8.0-1023.25~22.04.1

ubuntu/linux-azure<5.15.0-1094.103

5.15.0-1094.103

ubuntu/linux-azure-5.19*

ubuntu/linux-azure-6.2*

ubuntu/linux-azure-6.5*

ubuntu/linux-azure-6.8<6.8.0-1025.30~22.04.1

6.8.0-1025.30~22.04.1

ubuntu/linux-azure-fde<5.15.0-1094.103.1

5.15.0-1094.103.1

ubuntu/linux-azure-fde-5.19*

ubuntu/linux-azure-fde-6.2*

ubuntu/linux-gcp<5.15.0-1087.96

5.15.0-1087.96

ubuntu/linux-gcp-5.19*

ubuntu/linux-gcp-6.2*

ubuntu/linux-gcp-6.5*

ubuntu/linux-gcp-6.8<6.8.0-1024.26~22.04.1

6.8.0-1024.26~22.04.1

ubuntu/linux-gke<5.15.0-1085.91

5.15.0-1085.91

ubuntu/linux-gkeop<5.15.0-1070.78

5.15.0-1070.78

ubuntu/linux-hwe-5.19*

ubuntu/linux-hwe-6.2*

ubuntu/linux-hwe-6.5*

ubuntu/linux-hwe-6.8<6.8.0-57.59~22.04.1

6.8.0-57.59~22.04.1

ubuntu/linux-ibm<5.15.0-1080.83

5.15.0-1080.83

ubuntu/linux-ibm-6.8<6.8.0-1023.23~22.04.1

6.8.0-1023.23~22.04.1

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-intel-iotg<5.15.0-1083.89

5.15.0-1083.89

ubuntu/linux-kvm<5.15.0-1084.89

5.15.0-1084.89

ubuntu/linux-lowlatency<5.15.0-144.157

5.15.0-144.157

ubuntu/linux-lowlatency-hwe-5.19*

ubuntu/linux-lowlatency-hwe-6.2*

ubuntu/linux-lowlatency-hwe-6.5*

ubuntu/linux-lowlatency-hwe-6.8<6.8.0-54.56.1~22.04.1

6.8.0-54.56.1~22.04.1

ubuntu/linux-nvidia<5.15.0-1082.83

5.15.0-1082.83

ubuntu/linux-nvidia-6.2*

ubuntu/linux-nvidia-6.5*

ubuntu/linux-nvidia-6.8<6.8.0-1022.25~22.04.2

6.8.0-1022.25~22.04.2

ubuntu/linux-nvidia-tegra<5.15.0-1041.41

5.15.0-1041.41

ubuntu/linux-nvidia-tegra-igx<5.15.0-1030.30

5.15.0-1030.30

ubuntu/linux-oem-5.17*

ubuntu/linux-oem-6.0*

ubuntu/linux-oem-6.1*

ubuntu/linux-oem-6.5*

ubuntu/linux-oracle<5.15.0-1085.91

5.15.0-1085.91

ubuntu/linux-oracle-6.5*

ubuntu/linux-oracle-6.8<6.8.0-1020.21~22.04.1

6.8.0-1020.21~22.04.1

ubuntu/linux-raspi<5.15.0-1083.86

5.15.0-1083.86

ubuntu/linux-realtime*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.19*

ubuntu/linux-riscv-6.5*

ubuntu/linux-riscv-6.8<6.8.0-53.55.1~22.04.1

6.8.0-53.55.1~22.04.1

ubuntu/linux-starfive-5.19*

ubuntu/linux-starfive-6.2*

ubuntu/linux-starfive-6.5*

ubuntu/linux-xilinx-zynqmp<5.15.0-1052.56

5.15.0-1052.56

ubuntu/linux-bluefield<5.15.0-1072.74

5.15.0-1072.74

ubuntu/linux-intel-iot-realtime<5.15.0-1081.83

5.15.0-1081.83

ubuntu/linux-realtime<5.15.0-1088.97

5.15.0-1088.97

ubuntu/linux-realtime-6.8<6.8.1-1016.17~22.04.1

6.8.1-1016.17~22.04.1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-aws-fips<5.15.0-1088.95+fips1

5.15.0-1088.95+fips1

ubuntu/linux-azure-fips<5.15.0-1094.103+fips1

5.15.0-1094.103+fips1

ubuntu/linux-fips<5.15.0-144.157+fips1

5.15.0-144.157+fips1

ubuntu/linux-gcp-fips<5.15.0-1087.96+fips1

5.15.0-1087.96+fips1

ubuntu/linux<6.8.0-54.56

6.8.0-54.56

ubuntu/linux-aws<6.8.0-1023.25

6.8.0-1023.25

ubuntu/linux-azure<6.8.0-1025.30

6.8.0-1025.30

ubuntu/linux-azure-6.11<6.11.0-1012.12~24.04.1

6.11.0-1012.12~24.04.1

ubuntu/linux-azure-nvidia<6.8.0-1014.15

6.8.0-1014.15

ubuntu/linux-gcp<6.8.0-1024.26

6.8.0-1024.26

ubuntu/linux-gcp-6.11<6.11.0-1011.11~24.04.1

6.11.0-1011.11~24.04.1

ubuntu/linux-gke<6.8.0-1019.23

6.8.0-1019.23

ubuntu/linux-gkeop<6.8.0-1006.8

6.8.0-1006.8

ubuntu/linux-ibm<6.8.0-1022.22

6.8.0-1022.22

ubuntu/linux-lowlatency<6.8.0-54.56.1

6.8.0-54.56.1

ubuntu/linux-nvidia<6.8.0-1022.25

6.8.0-1022.25

ubuntu/linux-nvidia-6.11<6.11.0-1007.7

6.11.0-1007.7

ubuntu/linux-nvidia-lowlatency<6.8.0-1022.25.2

6.8.0-1022.25.2

ubuntu/linux-oem-6.11<6.11.0-1015.15

6.11.0-1015.15

ubuntu/linux-oem-6.8<6.8.0-1024.24

6.8.0-1024.24

ubuntu/linux-oracle<6.8.0-1020.21

6.8.0-1020.21

ubuntu/linux-raspi<6.8.0-1019.23

6.8.0-1019.23

ubuntu/linux-realtime*

ubuntu/linux-riscv<6.8.0-53.55.1

6.8.0-53.55.1

ubuntu/linux-xilinx<6.8.0-1017.18

6.8.0-1017.18

ubuntu/linux-raspi-realtime<6.8.0-2018.19

6.8.0-2018.19

ubuntu/linux-realtime<6.8.1-1016.17

6.8.1-1016.17

ubuntu/linux-fips<6.8.0-78.78+fips1

6.8.0-78.78+fips1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-aws-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95~20.04.1
Upgrade
Upgrade ubuntu/linux-azure-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103~20.04.1
Upgrade
Upgrade ubuntu/linux-gcp-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96~20.04.2
Upgrade
Upgrade ubuntu/linux-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157~20.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1080.83~20.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.89~20.04.1
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157~20.04.1
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1041.41~20.04.1
Upgrade
Upgrade ubuntu/linux-oracle-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91~20.04.3
Upgrade
Upgrade ubuntu/linux-riscv-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.87~20.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95
Upgrade
Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25~22.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103
Upgrade
Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.30~22.04.1
Upgrade
Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96
Upgrade
Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.26~22.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.15.0-1070.78
Upgrade
Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-57.59~22.04.1
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.15.0-1080.83
Upgrade
Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.23~22.04.1
Upgrade
Upgrade ubuntu/linux-intel-iotg to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.89
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.15.0-1084.89
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157
Upgrade
Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56.1~22.04.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 5.15.0-1082.83
Upgrade
Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25~22.04.2
Upgrade
Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.
Fixed in 5.15.0-1041.41
Upgrade
Upgrade ubuntu/linux-nvidia-tegra-igx to a version that resolves this vulnerability.
Fixed in 5.15.0-1030.30
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.15.0-1085.91
Upgrade
Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.21~22.04.1
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.15.0-1083.86
Upgrade
Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-53.55.1~22.04.1
Upgrade
Upgrade ubuntu/linux-xilinx-zynqmp to a version that resolves this vulnerability.
Fixed in 5.15.0-1052.56
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.15.0-1072.74
Upgrade
Upgrade ubuntu/linux-intel-iot-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1081.83
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.97
Upgrade
Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.1-1016.17~22.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1088.95+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1094.103+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-144.157+fips1
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.15.0-1087.96+fips1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 6.8.0-1023.25
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 6.8.0-1025.30
Upgrade
Upgrade ubuntu/linux-azure-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1012.12~24.04.1
Upgrade
Upgrade ubuntu/linux-azure-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1014.15
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.26
Upgrade
Upgrade ubuntu/linux-gcp-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1011.11~24.04.1
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.23
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 6.8.0-1006.8
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.22
Upgrade
Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-54.56.1
Upgrade
Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25
Upgrade
Upgrade ubuntu/linux-nvidia-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1007.7
Upgrade
Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.
Fixed in 6.8.0-1022.25.2
Upgrade
Upgrade ubuntu/linux-oem-6.11 to a version that resolves this vulnerability.
Fixed in 6.11.0-1015.15
Upgrade
Upgrade ubuntu/linux-oem-6.8 to a version that resolves this vulnerability.
Fixed in 6.8.0-1024.24
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 6.8.0-1020.21
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 6.8.0-1019.23
Upgrade
Upgrade ubuntu/linux-riscv to a version that resolves this vulnerability.
Fixed in 6.8.0-53.55.1
Upgrade
Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.
Fixed in 6.8.0-1017.18
Upgrade
Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.
Fixed in 6.8.0-2018.19
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 6.8.1-1016.17
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 6.8.0-78.78+fips1
Compensating control
Cancel the s_err_report timer after calling ext4_stop_mmpd, ensuring the timer is no longer active before kfree(sbi) during failed filesystem mounting.

Event History

Oct 21, 2024

CVE Published

via OSV·06:15 PM

Data Sourced

via OSV·06:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

What conditions are required to trigger the use-after-free?

An ext4 filesystem mount must fail, and the failed-mount path must encounter a read I/O error while ext4_stop_mmpd is called. That error can re-arm the filesystem error-reporting timer after the normal timer-cancellation step.

Is this remotely exploitable without access to the affected system?

The supplied CVSS vector rates attack vector as local and privileges required as low. Exploitation therefore requires local access with low privileges rather than unauthenticated remote access.

What is the consequence of the vulnerable cleanup path?

The ext4 error-reporting timer can remain active after the ext4 superblock information is freed, causing a timer use-after-free. The provided severity vector indicates potential high impact to confidentiality, integrity, and availability.

Which Ubuntu kernel packages are identified as affected?

The listed software includes ubuntu/linux-realtime, ubuntu/linux-azure, ubuntu/linux-gcp, ubuntu/linux-gke, ubuntu/linux-gkeop, ubuntu/linux-riscv, ubuntu/linux-fips, and ubuntu/linux-hwe-edge.

UBUNTU-CVE-2024-49960: Use After Free

Affected Software

Remediation

Event History

Frequently Asked Questions

What conditions are required to trigger the use-after-free?

Is this remotely exploitable without access to the affected system?

What is the consequence of the vulnerable cleanup path?

Which Ubuntu kernel packages are identified as affected?

Company

Resources

Contact

Frequently Asked Questions

What conditions are required to trigger the use-after-free?

Is this remotely exploitable without access to the affected system?

What is the consequence of the vulnerable cleanup path?

Which Ubuntu kernel packages are identified as affected?