Ubuntu update for linux

1) Integer overflow

EUVDB-ID: #VU55143

Risk: Low

CVSSv4.0: 7.1 [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:P/U:Clear]

CVE-ID: CVE-2021-33909

CWE-ID: CWE-190 - Integer overflow

Exploit availability: Yes

Description

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

The vulnerability exists due to integer overflow during size_t-to-int conversion when creating, mounting, and deleting a deep directory structure whose total path length exceeds 1GB. An unprivileged local user can write up to 10-byte string to an offset of exactly -2GB-10B below the beginning of a vmalloc()ated kernel buffer.

Successful exploitation of vulnerability may allow an attacker to exploit the our-of-bounds write vulnerability to execute arbitrary code with root privileges.

Mitigation

Update the affected package linux to the latest version.

Vulnerable software versions

Ubuntu: 14.04 - 21.04

linux-image-raspi (Ubuntu package): before 5.11.0.1015.13

linux-image-virtual (Ubuntu package): before 5.11.0.25.27

linux-image-raspi-nolpae (Ubuntu package): before 5.11.0.1015.13

linux-image-oracle (Ubuntu package): before 5.11.0.1013.14

linux-image-oem-20.04 (Ubuntu package): before 5.11.0.25.27

linux-image-lowlatency (Ubuntu package): before 5.11.0.25.27

linux-image-kvm (Ubuntu package): before 5.11.0.1012.13

linux-image-gke (Ubuntu package): before 5.11.0.1014.14

linux-image-generic-lpae (Ubuntu package): before 5.11.0.25.27

linux-image-generic-64k (Ubuntu package): before 5.11.0.25.27

linux-image-generic (Ubuntu package): before 5.11.0.25.27

linux-image-gcp (Ubuntu package): before 5.11.0.1014.14

linux-image-azure (Ubuntu package): before 5.11.0.1012.13

linux-image-aws (Ubuntu package): before 5.11.0.1014.15

linux-image-5.11.0-25-lowlatency (Ubuntu package): before 5.11.0-25.27

linux-image-5.11.0-25-generic-lpae (Ubuntu package): before 5.11.0-25.27

linux-image-5.11.0-25-generic-64k (Ubuntu package): before 5.11.0-25.27

linux-image-5.11.0-25-generic (Ubuntu package): before 5.11.0-25.27

linux-image-5.11.0-1015-raspi-nolpae (Ubuntu package): before 5.11.0-1015.16

linux-image-5.11.0-1015-raspi (Ubuntu package): before 5.11.0-1015.16

linux-image-5.11.0-1014-gcp (Ubuntu package): before 5.11.0-1014.16

linux-image-5.11.0-1014-aws (Ubuntu package): before 5.11.0-1014.15

linux-image-5.11.0-1013-oracle (Ubuntu package): before 5.11.0-1013.14

linux-image-5.11.0-1012-kvm (Ubuntu package): before 5.11.0-1012.13

linux-image-5.11.0-1012-azure (Ubuntu package): before 5.11.0-1012.13

linux-image-virtual-lts-xenial (Ubuntu package): before 4.4.0.210.183

linux-image-lowlatency-lts-xenial (Ubuntu package): before 4.4.0.210.183

linux-image-generic-lts-xenial (Ubuntu package): before 4.4.0.210.183

linux-image-server (Ubuntu package): before 3.13.0.184.193

linux-image-powerpc64-smp (Ubuntu package): before 3.13.0.184.193

linux-image-powerpc64-emb (Ubuntu package): before 3.13.0.184.193

linux-image-powerpc-smp (Ubuntu package): before 3.13.0.184.193

linux-image-powerpc-e500mc (Ubuntu package): before 3.13.0.184.193

linux-image-powerpc-e500 (Ubuntu package): before 3.13.0.184.193

linux-image-omap (Ubuntu package): before 3.13.0.184.193

linux-image-lowlatency-pae (Ubuntu package): before 3.13.0.184.193

linux-image-highbank (Ubuntu package): before 3.13.0.184.193

linux-image-generic-pae (Ubuntu package): before 3.13.0.184.193

linux-image-raspi2-hwe-18.04 (Ubuntu package): before 5.3.0.1042.31

linux-image-gkeop-5.3 (Ubuntu package): before 5.3.0.76.133

linux-image-gke-5.3 (Ubuntu package): before 5.3.0.1045.28

linux-image-5.3.0-76-lowlatency (Ubuntu package): before 5.3.0-76.72

linux-image-5.3.0-76-generic (Ubuntu package): before 5.3.0-76.72

linux-image-5.3.0-1045-gke (Ubuntu package): before 5.3.0-1045.48

linux-image-5.3.0-1042-raspi2 (Ubuntu package): before 5.3.0-1042.44

linux-image-4.4.0-1094-aws (Ubuntu package): before 4.4.0-1094.105

CPE2.3

• cpe:2.3:o:canonical:ubuntu:14.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:18.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:21.04:*:*:*:*:*:*:*
• cpe:2.3:a:canonical:linux-image-raspi_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-oem-20.04:*:*:*:*:*: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-5.11.0-25-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-25-generic-lpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-25-generic-64k_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-25-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1015-raspi-nolpae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1015-raspi_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1014-gcp_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1014-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1013-oracle_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1012-kvm_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.11.0-1012-azure_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-virtual-lts-xenial_ubuntu_package:*:*:*:*:*: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-server:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-powerpc64-smp_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-powerpc64-emb_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-powerpc-smp_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-powerpc-e500mc_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-powerpc-e500_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-omap_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-lowlatency-pae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-highbank_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-generic-pae_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-raspi2-hwe-18.04_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-gkeop-5.3_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-gke-5.3_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.3.0-76-lowlatency_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.3.0-76-generic_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.3.0-1045-gke_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-5.3.0-1042-raspi2_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:a:canonical:linux-image-4.4.0-1094-aws_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://ubuntu.com/security/notices/USN-5014-1

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?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.