Amazon Linux 2 : kernel (ALAS-2021-1696)

medium Nessus Plugin ID 152238

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 4.14.241-184.433. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2021-1696 advisory.

A flaw was found in the Linux kernel, where an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack. This issue occurs when the protection mechanism neglects the possibility of uninitialized memory locations on the BPF stack. The highest threat from this vulnerability is to confidentiality. (CVE-2021-34556)

A flaw in the Linux kernel allows a privileged BPF program to obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel in the eBPF subsystem (CVE-2021-35477)

A vulnerability was found in the Linux kernel. Missing size validations on inbound SCTP packets may allow the kernel to read uninitialized memory. (CVE-2021-3655)

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

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/ALAS-2021-1696.html

https://access.redhat.com/security/cve/CVE-2021-34556

https://access.redhat.com/security/cve/CVE-2021-35477

https://access.redhat.com/security/cve/CVE-2021-3655

Plugin Details

Severity: Medium

ID: 152238

File Name: al2_ALAS-2021-1696.nasl

Version: 1.5

Type: local

Agent: unix

Published: 8/6/2021

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: Low

Base Score: 2.1

Temporal Score: 1.6

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

CVSS Score Source: CVE-2021-3655

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

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

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

CVSS Score Source: CVE-2021-35477

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:python-perf-debuginfo, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-livepatch-4.14.241-184.433, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:python-perf

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

Exploit Ease: No known exploits are available

Patch Publication Date: 8/4/2021

Vulnerability Publication Date: 8/2/2021

Reference Information

CVE: CVE-2021-34556, CVE-2021-35477, CVE-2021-3655

ALAS: 2021-1696