Amazon Linux AMI : chrony (ALAS-2020-1431)

medium Nessus Plugin ID 140206
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Synopsis

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

Description

The version of tested product installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the ALAS-2020-1431 advisory.

- A flaw was found in chrony versions before 3.5.1 when creating the PID file under the /var/run/chrony folder. The file is created during chronyd startup while still running as the root user, and when it's opened for writing, chronyd does not check for an existing symbolic link with the same file name. This flaw allows an attacker with privileged access to create a symlink with the default PID file name pointing to any destination file in the system, resulting in data loss and a denial of service due to the path traversal. (CVE-2020-14367)

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 chrony' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2020-1431.html

https://access.redhat.com/security/cve/CVE-2020-14367

Plugin Details

Severity: Medium

ID: 140206

File Name: ala_ALAS-2020-1431.nasl

Version: 1.1

Type: local

Agent: unix

Published: 9/4/2020

Updated: 9/4/2020

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2020-14367

VPR

Risk Factor: Medium

Score: 6

CVSS v2

Risk Factor: Low

Base Score: 3.6

Temporal Score: 2.7

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

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

CVSS v3

Risk Factor: Medium

Base Score: 6

Temporal Score: 5.2

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

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:chrony, p-cpe:/a:amazon:linux:chrony-debuginfo, cpe:/o:amazon:linux

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

Exploit Ease: No known exploits are available

Patch Publication Date: 9/3/2020

Vulnerability Publication Date: 8/24/2020

Reference Information

CVE: CVE-2020-14367

ALAS: 2020-1431