Amazon Linux 2 : kernel (ALASKERNEL-5.4-2023-050)

high Nessus Plugin ID 179775

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 5.4.250-166.369. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.4-2023-050 advisory.

- An issue in Zen 2 CPUs, under specific microarchitectural circumstances, may allow an attacker to potentially access sensitive information. (CVE-2023-20593)

- An out-of-bounds write vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. The qfq_change_agg() function in net/sched/sch_qfq.c allows an out- of-bounds write because lmax is updated according to packet sizes without bounds checks. We recommend upgrading past commit 3e337087c3b5805fe0b8a46ba622a962880b5d64. (CVE-2023-3611)

- A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. If tcf_change_indev() fails, fw_set_parms() will immediately return an error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can control the reference counter and set it to zero, they can cause the reference to be freed, leading to a use-after-free vulnerability. We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.
(CVE-2023-3776)

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-5.4-2023-050.html

https://alas.aws.amazon.com/faqs.html

https://alas.aws.amazon.com/cve/html/CVE-2023-20569.html

https://alas.aws.amazon.com/cve/html/CVE-2023-3611.html

https://alas.aws.amazon.com/cve/html/CVE-2023-3776.html

https://alas.aws.amazon.com/cve/html/CVE-2023-20593.html

Plugin Details

Severity: High

ID: 179775

File Name: al2_ALASKERNEL-5_4-2023-050.nasl

Version: 1.3

Type: local

Agent: unix

Published: 8/14/2023

Updated: 10/20/2023

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2023-3776

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

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

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:python-perf, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:bpftool-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:bpftool, p-cpe:/a:amazon:linux:python-perf-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, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-debuginfo

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/3/2023

Vulnerability Publication Date: 7/21/2023

Reference Information

CVE: CVE-2023-20569, CVE-2023-20593, CVE-2023-3611, CVE-2023-3776