Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2024-493)

high Nessus Plugin ID 189330

Synopsis

The remote Amazon Linux 2023 host is missing a security update.

Description

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2024-493 advisory.

When a router encounters an IPv6 packet too big to transmit to the next-hop, it returns an ICMP6 Packet Too Big (PTB) message to the sender. The sender caches this updated Maximum Transmission Unit (MTU) so it knows not to exceed this value when subsequently routing to the same host.

In Linux kernels prior to 6.3, garbage collection is run on the IPv6 Destination Route Cache if the number of entries exceeds a threshold when adding the destination to the cache. This garbage collection examines every entry in the cache while holding a lock. In these affected kernel versions, a flood of the IPv6 ICMP6 PTB messages could cause high lock contention and increased CPU usage, leading to a Denial-of- Service.

The fix backports the garbage collection improvements from Linux kernel 6.3 by bringing the IPv6 code closer to the IPv4 code, which does not have this issue.

Patch: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=af6d10345ca76670c1b7c3 7799f0d5576ccef277 (CVE-2023-52340)

Tenable has extracted the preceding description block directly from the tested product security advisory.

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

Solution

Run 'dnf update kernel --releasever 2023.3.20240122' to update your system.

See Also

https://alas.aws.amazon.com/AL2023/ALAS-2024-493.html

https://alas.aws.amazon.com/cve/html/CVE-2023-52340.html

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

Plugin Details

Severity: High

ID: 189330

File Name: al2023_ALAS2023-2024-493.nasl

Version: 1.2

Type: local

Agent: unix

Published: 1/23/2024

Updated: 12/11/2024

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

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2023-52340

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:kernel-modules-extra-common, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-modules-extra, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:python3-perf, p-cpe:/a:amazon:linux:kernel-libbpf-static, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-libbpf, p-cpe:/a:amazon:linux:bpftool-debuginfo, p-cpe:/a:amazon:linux:kernel-livepatch-6.1.66-93.164, p-cpe:/a:amazon:linux:kernel-libbpf-devel, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-tools-devel, cpe:/o:amazon:linux:2023, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:bpftool, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:python3-perf-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64

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

Exploit Ease: No known exploits are available

Patch Publication Date: 1/19/2024

Vulnerability Publication Date: 1/19/2024

Reference Information

CVE: CVE-2023-52340