Amazon Linux AMI : zsh (ALAS-2018-1107)

critical Nessus Plugin ID 119466

Synopsis

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

Description

A buffer overflow flaw was found in the zsh shell symbolic link resolver. A local, unprivileged user can create a specially crafted directory path which leads to a buffer overflow in the context of the user trying to do a symbolic link resolution in the aforementioned path. If the user affected is privileged, this leads to privilege escalation.(CVE-2017-18206)

A buffer overflow flaw was found in the zsh shell auto-complete functionality. A local, unprivileged user can create a specially crafted directory path which leads to code execution in the context of the user who tries to use auto-complete to traverse the before mentioned path. If the user affected is privileged, this leads to privilege escalation.(CVE-2018-1083)

A NULL pointer dereference flaw was found in the code responsible for saving hashtables of the zsh package. An attacker could use this flaw to cause a denial of service by crashing the user shell.(CVE-2018-7549)

A NULL pointer dereference flaw was found in the code responsible for the cd builtin command of the zsh package. An attacker could use this flaw to cause a denial of service by crashing the user shell.(CVE-2017-18205)

A buffer overflow flaw was found in the zsh shell symbolic link resolver. A local, unprivileged user can create a specially crafted directory path which leads to a buffer overflow in the context of the user trying to do symbolic link resolution in the aforementioned path.
An attacker could exploit this vulnerability to cause a denial of service condition on the target.(CVE-2014-10072)

A buffer overflow flaw was found in the zsh shell check path functionality. A local, unprivileged user can create a specially crafted message file, which, if used to set a custom 'you have new mail' message, leads to code execution in the context of the user who receives the message. If the user affected is privileged, this leads to privilege escalation.(CVE-2018-1100)

zsh through version 5.4.2 is vulnerable to a stack-based buffer overflow in the exec.c:hashcmd() function. A local attacker could exploit this to cause a denial of service.(CVE-2018-1071)

A buffer overflow flaw was found in the zsh shell file descriptor redirection functionality. An attacker could use this flaw to cause a denial of service by crashing the user shell.(CVE-2014-10071)

Solution

Run 'yum update zsh' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2018-1107.html

Plugin Details

Severity: Critical

ID: 119466

File Name: ala_ALAS-2018-1107.nasl

Version: 1.3

Type: local

Agent: unix

Published: 12/7/2018

Updated: 6/9/2020

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

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

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

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: CVSS:3.0/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: 12/7/2018

Vulnerability Publication Date: 2/27/2018

Reference Information

CVE: CVE-2014-10071, CVE-2014-10072, CVE-2017-18205, CVE-2017-18206, CVE-2018-1071, CVE-2018-1083, CVE-2018-1100, CVE-2018-7549

ALAS: 2018-1107