Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-020)

high Nessus Plugin ID 160427

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of kernel installed on the remote host is prior to 5.4.95-42.163. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.4-2022-020 advisory.

- A use-after-free flaw was found in kernel/trace/ring_buffer.c in Linux kernel (before 5.10-rc1). There was a race problem in trace_open and resize of cpu buffer running parallely on different cpus, may cause a denial of service problem (DOS). This flaw could even allow a local attacker with special user privilege to a kernel information leak threat. (CVE-2020-27825)

- ** DISPUTED ** fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior. (CVE-2021-3178)

- An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458.
(CVE-2021-3347)

- nbd_add_socket in drivers/block/nbd.c in the Linux kernel through 5.10.12 has an ndb_queue_rq use-after- free that could be triggered by local attackers (with access to the nbd device) via an I/O request at a certain point during device setup, aka CID-b98e762e3d71. (CVE-2021-3348)

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

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALASKERNEL-5.4-2022-020.html

https://alas.aws.amazon.com/cve/html/CVE-2020-27825.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3178.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3347.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3348.html

Plugin Details

Severity: High

ID: 160427

File Name: al2_ALASKERNEL-5_4-2022-020.nasl

Version: 1.3

Type: local

Agent: unix

Published: 5/2/2022

Updated: 6/7/2022

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

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

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

CVSS Score Source: CVE-2021-3347

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: p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:python-perf, p-cpe:/a:amazon:linux:python-perf-debuginfo, cpe:/o:amazon:linux:2

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 1/20/2022

Vulnerability Publication Date: 12/11/2020

Reference Information

CVE: CVE-2020-27825, CVE-2021-3178, CVE-2021-3347, CVE-2021-3348