Ubuntu 20.04 LTS : Linux kernel (OEM) vulnerabilities (USN-5217-1)

high Nessus Plugin ID 156612

Synopsis

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

Description

The remote Ubuntu 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-5217-1 advisory.

- An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel. Missing sanity may lead to a write beyond bmval[bmlen-1] in nfsd4_decode_bitmap4 in fs/nfsd/nfs4xdr.c. In this flaw, a local attacker with user privilege may gain access to out-of-bounds memory, leading to a system integrity and confidentiality threat. (CVE-2021-4090)

- An out-of-bounds (OOB) memory access flaw was found in the Linux kernel's eBPF due to an Improper Input Validation. This flaw allows a local attacker with a special privilege to crash the system or leak internal information. (CVE-2021-4204)

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

Solution

Update the affected kernel package.

See Also

https://ubuntu.com/security/notices/USN-5217-1

Plugin Details

Severity: High

ID: 156612

File Name: ubuntu_USN-5217-1.nasl

Version: 1.8

Type: local

Agent: unix

Published: 1/11/2022

Updated: 1/9/2024

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: Medium

Base Score: 6.6

Temporal Score: 4.9

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:N

CVSS Score Source: CVE-2021-4090

CVSS v3

Risk Factor: High

Base Score: 7.1

Temporal Score: 6.2

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS Score Source: CVE-2021-4204

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:linux-image-5.14.0-1018-oem

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

Exploit Ease: No known exploits are available

Patch Publication Date: 1/11/2022

Vulnerability Publication Date: 1/11/2022

Reference Information

CVE: CVE-2021-4090, CVE-2021-4204

USN: 5217-1