Detections
Analytics

Amazon Linux AMI : ntp (ALAS-2016-727)

medium Nessus Plugin ID 92662

Language:

Synopsis

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

Description

It was discovered that ntpq and ntpdc disclosed the origin timestamp to unauthenticated clients, which could permit such clients to forge the server's replies. (CVE-2015-8139)

The process_packet function in ntp_proto.c in ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (peer-variable modification) by sending spoofed packets from many source IP addresses in a certain scenario, as demonstrated by triggering an incorrect leap indication. (CVE-2016-4954)

ntpd in NTP 4.x before 4.2.8p8, when autokey is enabled, allows remote attackers to cause a denial of service (peer-variable clearing and association outage) by sending (1) a spoofed crypto-NAK packet or (2) a packet with an incorrect MAC value at a certain time.
(CVE-2016-4955)

ntpd in NTP 4.x before 4.2.8p8 allows remote attackers to cause a denial of service (interleaved-mode transition and time change) via a spoofed broadcast packet. This vulnerability exists because of an incomplete fix for CVE-2016-1548 . (CVE-2016-4956)

Solution

Run 'yum update ntp' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2016-727.html

Plugin Details

Severity: Medium

ID: 92662

File Name: ala_ALAS-2016-727.nasl

Version: 2.10

Type: local

Agent: unix

Published: 8/2/2016

Updated: 1/29/2026

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: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2015-8139

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

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

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:ntpdate, p-cpe:/a:amazon:linux:ntp, p-cpe:/a:amazon:linux:ntp-debuginfo, p-cpe:/a:amazon:linux:ntp-perl, cpe:/o:amazon:linux, p-cpe:/a:amazon:linux:ntp-doc

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

Exploit Ease: No known exploits are available

Patch Publication Date: 1/4/2017

Vulnerability Publication Date: 7/5/2016

Reference Information

CVE: CVE-2015-8139, CVE-2016-4954, CVE-2016-4955, CVE-2016-4956

ALAS: 2016-727