Amazon Linux AMI : zsh (ALAS-2019-1285)

critical Nessus Plugin ID 129012
New! Plugin Severity Now Using CVSS v3

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Synopsis

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

Description

It was discovered that zsh does not properly validate the shebang of input files and it truncates it to the first 64 bytes. A local attacker may use this flaw to make zsh execute a different binary than what is expected, named with a substring of the shebang one.(CVE-2018-13259)

Solution

Run 'yum update zsh' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2019-1285.html

Plugin Details

Severity: Critical

ID: 129012

File Name: ala_ALAS-2019-1285.nasl

Version: 1.2

Type: local

Agent: unix

Published: 9/19/2019

Updated: 12/27/2019

Dependencies: ssh_get_info.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

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

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

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/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:zsh, p-cpe:/a:amazon:linux:zsh-debuginfo, p-cpe:/a:amazon:linux:zsh-html, 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: 9/18/2019

Vulnerability Publication Date: 9/5/2018

Reference Information

CVE: CVE-2018-13259

ALAS: 2019-1285