Ubuntu update for linux

1) Improper Privilege Management

EUVDB-ID: #VU52036

Risk: Low

CVSSv4.0: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Clear]

CVE-ID: CVE-2021-26708

CWE-ID: CWE-269 - Improper Privilege Management

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges.

The vulnerability exists due to improper privilege management. Multiple race conditions in the AF_VSOCK implementation are caused by wrong locking in net/vmw_vsock/af_vsock.c. The race conditions were implicitly introduced in the commits that added VSOCK multi-transport support.

Mitigation

Update the affected package linux to the latest version.

Vulnerable software versions

Ubuntu: 20.04 - 20.10

linux-image-raspi (Ubuntu package): before 5.8.0.1015.18

linux-image-virtual-hwe-20.04 (Ubuntu package): before 5.8.0.43.49~20.04.29

linux-image-oem-20.04 (Ubuntu package): before 5.6.0.1047.43

linux-image-lowlatency-hwe-20.04 (Ubuntu package): before 5.8.0.43.49~20.04.29

linux-image-generic-lpae-hwe-20.04 (Ubuntu package): before 5.8.0.43.49~20.04.29

linux-image-generic-hwe-20.04 (Ubuntu package): before 5.8.0.43.49~20.04.29

linux-image-generic-64k-hwe-20.04 (Ubuntu package): before 5.8.0.43.49~20.04.29

linux-image-5.6.0-1047-oem (Ubuntu package): before 5.6.0-1047.51

linux-image-virtual (Ubuntu package): before 5.8.0.43.48

linux-image-raspi-nolpae (Ubuntu package): before 5.8.0.1015.18

linux-image-oracle (Ubuntu package): before 5.8.0.1020.19

linux-image-lowlatency (Ubuntu package): before 5.8.0.43.48

linux-image-kvm (Ubuntu package): before 5.8.0.1018.20

linux-image-gke (Ubuntu package): before 5.8.0.1022.22

linux-image-generic-lpae (Ubuntu package): before 5.8.0.43.48

linux-image-generic-64k (Ubuntu package): before 5.8.0.43.48

linux-image-generic (Ubuntu package): before 5.8.0.43.48

linux-image-gcp (Ubuntu package): before 5.8.0.1022.22

linux-image-azure (Ubuntu package): before 5.8.0.1022.22

linux-image-aws (Ubuntu package): before 5.8.0.1023.25

linux-image-5.8.0-43-lowlatency (Ubuntu package): before 5.8.0-43.49~20.04.1

linux-image-5.8.0-43-generic-lpae (Ubuntu package): before 5.8.0-43.49~20.04.1

linux-image-5.8.0-43-generic-64k (Ubuntu package): before 5.8.0-43.49

linux-image-5.8.0-43-generic (Ubuntu package): before 5.8.0-43.49~20.04.1

linux-image-5.8.0-1023-aws (Ubuntu package): before 5.8.0-1023.25

linux-image-5.8.0-1022-gcp (Ubuntu package): before 5.8.0-1022.23

linux-image-5.8.0-1022-azure (Ubuntu package): before 5.8.0-1022.24

linux-image-5.8.0-1020-oracle (Ubuntu package): before 5.8.0-1020.21

linux-image-5.8.0-1018-kvm (Ubuntu package): before 5.8.0-1018.20

linux-image-5.8.0-1015-raspi-nolpae (Ubuntu package): before 5.8.0-1015.18

linux-image-5.8.0-1015-raspi (Ubuntu package): before 5.8.0-1015.18

CPE2.3

• cpe:2.3:o:canonical:ubuntu:20.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:20.10:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:linux-image-raspi_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-virtual-hwe-20.04:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-oem-20.04:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-lowlatency-hwe-20.04:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-lpae-hwe-20.04_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-hwe-20.04:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-64k-hwe-20.04_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.6.0-1047-oem_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-virtual_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-raspi-nolpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-oracle_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-kvm_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-gke_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-lpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-64k_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-gcp_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-azure_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-43-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-43-generic-lpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-43-generic-64k_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-43-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1023-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1022-gcp_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1022-azure_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1020-oracle_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1018-kvm_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1015-raspi-nolpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.8.0-1015-raspi_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-4727-1

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.