Ubuntu update for linux

1) Out-of-bounds write

EUVDB-ID: #VU56017

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-2021-22555

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a boundary error when processing untrusted input in net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.

Mitigation

Update the affected package linux to the latest version.

Vulnerable software versions

Ubuntu: 14.04 - 16.04

linux-image-virtual-lts-xenial (Ubuntu package): before 4.4.01096.105

linux-image-server (Ubuntu package): before 4.4.01096.105

linux-image-lowlatency-lts-xenial (Ubuntu package): before 4.4.01096.105

linux-image-generic-lts-xenial (Ubuntu package): before 4.4.01096.105

linux-image-generic-lpae (Ubuntu package): before 4.4.01096.105

linux-image-4.4.0-1095-aws (Ubuntu package): before 4.4.01096.105

linux-image-3.13.0-187-lowlatency (Ubuntu package): before 4.4.01096.105

linux-image-3.13.0-187-generic-lpae (Ubuntu package): before 4.4.01096.105

linux-image-3.13.0-187-generic (Ubuntu package): before 4.4.01096.105

linux-image-virtual (Ubuntu package): before 4.4.01096.105

linux-image-lowlatency (Ubuntu package): before 4.4.01096.105

linux-image-kvm (Ubuntu package): before 4.4.01096.105

linux-image-generic (Ubuntu package): before 4.4.01096.105

linux-image-aws (Ubuntu package): before 4.4.01096.105

linux-image-4.4.0-213-lowlatency (Ubuntu package): before 4.4.01096.105

linux-image-4.4.0-213-generic (Ubuntu package): before 4.4.01096.105

linux-image-4.4.0-1131-aws (Ubuntu package): before 4.4.01096.105

linux-image-4.4.0-1096-kvm (Ubuntu package): before 4.4.01096.105

CPE2.3

• cpe:2.3:o:canonical:ubuntu:14.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:linux-image-virtual-lts-xenial_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-server:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-lowlatency-lts-xenial_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-lts-xenial_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-lpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-1095-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-3.13.0-187-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-3.13.0-187-generic-lpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-3.13.0-187-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-virtual_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-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-213-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-213-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-1131-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-1096-kvm_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-5039-1

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.