Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-4576-1)

high Nessus Plugin ID 141451

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-4576-1 advisory.

- A memory out-of-bounds read flaw was found in the Linux kernel before 5.9-rc2 with the ext3/ext4 file system, in the way it accesses a directory with broken indexing. This flaw allows a local user to crash the system if the directory exists. The highest threat from this vulnerability is to system availability.
(CVE-2020-14314)

- A flaw was found in the Linux kernel before 5.9-rc4. A failure of the file system metadata validator in XFS can cause an inode with a valid, user-creatable extended attribute to be flagged as corrupt. This can lead to the filesystem being shutdown, or otherwise rendered inaccessible until it is remounted, leading to a denial of service. The highest threat from this vulnerability is to system availability.
(CVE-2020-14385)

- A race condition between hugetlb sysctl handlers in mm/hugetlb.c in the Linux kernel before 5.8.8 could be used by local attackers to corrupt memory, cause a NULL pointer dereference, or possibly have unspecified other impact, aka CID-17743798d812. (CVE-2020-25285)

- A flaw was found in the Linux kernel's implementation of biovecs in versions before 5.9-rc7. A zero-length biovec request issued by the block subsystem could cause the kernel to enter an infinite loop, causing a denial of service. This flaw allows a local attacker with basic privileges to issue requests to a block device, resulting in a denial of service. The highest threat from this vulnerability is to system availability. (CVE-2020-25641)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-4576-1

Plugin Details

Severity: High

ID: 141451

File Name: ubuntu_USN-4576-1.nasl

Version: 1.4

Type: local

Agent: unix

Published: 10/14/2020

Updated: 1/26/2021

Supported Sensors: Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS Score Source: CVE-2020-16119

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:18.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1021-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1026-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1028-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1028-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1028-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-1031-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-51-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-51-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.4.0-51-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws, p-cpe:/a:canonical:ubuntu_linux:linux-image-aws-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-azure, p-cpe:/a:canonical:ubuntu_linux:linux-image-azure-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-gcp, p-cpe:/a:canonical:ubuntu_linux:linux-image-gcp-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-gke, p-cpe:/a:canonical:ubuntu_linux:linux-image-kvm, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency-hwe-20.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-osp1, p-cpe:/a:canonical:ubuntu_linux:linux-image-oracle, p-cpe:/a:canonical:ubuntu_linux:linux-image-oracle-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-snapdragon-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-snapdragon-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-18.04, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-18.04-edge, p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual-hwe-20.04

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 10/14/2020

Vulnerability Publication Date: 9/13/2020

Reference Information

CVE: CVE-2020-14314, CVE-2020-14385, CVE-2020-16119, CVE-2020-16120, CVE-2020-25285, CVE-2020-25641

USN: 4576-1