Ubuntu 20.04 LTS : Linux kernel (OEM) vulnerability (USN-4683-1)

medium Nessus Plugin ID 144786
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Synopsis

The remote Ubuntu host is missing a security update.

Description

The remote Ubuntu 20.04 LTS host has packages installed that are affected by a vulnerability as referenced in the USN-4683-1 advisory.

- A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height. (CVE-2020-28974)

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 linux-image-5.6.0-1039-oem and / or linux-image-oem-20.04 packages.

See Also

https://ubuntu.com/security/notices/USN-4683-1

Plugin Details

Severity: Medium

ID: 144786

File Name: ubuntu_USN-4683-1.nasl

Version: 1.4

Type: local

Agent: unix

Published: 1/7/2021

Updated: 1/28/2021

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

CVSS Score Source: CVE-2020-28974

VPR

Risk Factor: Medium

Score: 5.5

CVSS v2

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 4.5

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

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

CVSS v3

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.4

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

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.6.0-1039-oem, p-cpe:/a:canonical:ubuntu_linux:linux-image-oem-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: 1/7/2021

Vulnerability Publication Date: 11/19/2020

Reference Information

CVE: CVE-2020-28974

USN: 4683-1