Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-031)

high Nessus Plugin ID 163387

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 5.4.156-83.273. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.4-2022-031 advisory.

- A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.
(CVE-2021-20321)

- A memory leak flaw was found in the Linux kernel in the ccp_run_aes_gcm_cmd() function in drivers/crypto/ccp/ccp-ops.c, which allows attackers to cause a denial of service (memory consumption).
This vulnerability is similar with the older CVE-2019-18808. (CVE-2021-3744)

- prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel before 5.14.12 allows unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds write. (CVE-2021-41864)

- kernel: DoS in ccp_run_aes_gcm_cmd() function (CVE-2021-3764)

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-5.4-2022-031.html

https://alas.aws.amazon.com/cve/html/CVE-2021-20321.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3744.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3764.html

https://alas.aws.amazon.com/cve/html/CVE-2021-41864.html

Plugin Details

Severity: High

ID: 163387

File Name: al2_ALASKERNEL-5_4-2022-031.nasl

Version: 1.2

Type: local

Agent: unix

Published: 7/22/2022

Updated: 7/22/2022

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

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

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

CVSS Score Source: CVE-2021-41864

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:bpftool, p-cpe:/a:amazon:linux:bpftool-debuginfo, 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: 7/19/2022

Vulnerability Publication Date: 10/2/2021

Reference Information

CVE: CVE-2021-3744, CVE-2021-3764, CVE-2021-20321, CVE-2021-41864