Amazon Linux AMI : kernel (ALAS-2021-1524)

high Nessus Plugin ID 151934
New! Plugin Severity Now Using CVSS v3

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Synopsis

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

Description

The version of kernel installed on the remote host is prior to 4.14.238-125.422. It is, therefore, affected by a vulnerability as referenced in the ALAS-2021-1524 advisory.

- fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05. (CVE-2021-33909)

Note that Nessus has not tested for this issue 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/ALAS-2021-1524.html

https://access.redhat.com/security/cve/CVE-2021-33909

Plugin Details

Severity: High

ID: 151934

File Name: ala_ALAS-2021-1524.nasl

Version: 1.6

Type: local

Agent: unix

Published: 7/22/2021

Updated: 7/30/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2021-33909

VPR

Risk Factor: Critical

Score: 9.7

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.3

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

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

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.5

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

Temporal Vector: E:H/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-i686, 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, cpe:/o:amazon:linux

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: 7/20/2021

Vulnerability Publication Date: 7/20/2021

Reference Information

CVE: CVE-2021-33909

ALAS: 2021-1524

IAVA: 2021-A-0350