Network Time Protocol Daemon (ntpd) 4.x < 4.2.8p8 / 4.3.x < 4.3.93 Multiple Vulnerabilities

Medium Nessus Plugin ID 91515

Synopsis

The remote NTP server is affected by multiple vulnerabilities.

Description

The version of the remote NTP server is 4.x prior to 4.2.8p8 or 4.3.x prior to 4.3.93. It is, therefore, affected by the following vulnerabilities :
- A denial of service vulnerability exists when handling authentication due to improper packet timestamp checks.
An unauthenticated, remote attacker can exploit this, via a specially crafted and spoofed packet, to demobilize the ephemeral associations. (CVE-2016-4953)

- A flaw exists that is triggered when handling spoofed packets. An unauthenticated, remote attacker can exploit this, via specially crafted packets, to affect peer variables (e.g., cause leap indications to be set). Note that the attacker must be able to spoof packets with correct origin timestamps from servers before expected response packets arrive. (CVE-2016-4954)

- A flaw exists that is triggered when handling spoofed packets. An unauthenticated, remote attacker can exploit this, via specially crafted packets, to reset autokey associations. Note that the attacker must be able to spoof packets with correct origin timestamps from servers before expected response packets arrive.
(CVE-2016-4955)

- A flaw exists when handling broadcast associations that allows an unauthenticated, remote attacker to cause a broadcast client to change into interleave mode.
(CVE-2016-4956)

- A denial of service vulnerability exists when handling CRYPTO_NAK packets that allows an unauthenticated, remote attacker to cause a crash. Note that this issue only affects versions 4.2.8p7 and 4.3.92.
(CVE-2016-4957)

Solution

Upgrade to NTP version 4.2.8p8 / 4.3.93 or later.

See Also

http://support.ntp.org/bin/view/Main/SecurityNotice

http://www.nessus.org/u?7bd9ab96

http://support.ntp.org/bin/view/Main/NtpBug3042

http://support.ntp.org/bin/view/Main/NtpBug3043

http://support.ntp.org/bin/view/Main/NtpBug3044

http://support.ntp.org/bin/view/Main/NtpBug3045

http://support.ntp.org/bin/view/Main/NtpBug3046

Plugin Details

Severity: Medium

ID: 91515

File Name: ntp_4_2_8p8.nasl

Version: 1.9

Type: remote

Family: Misc.

Published: 2016/06/08

Updated: 2019/11/14

Dependencies: 10884

Configuration: Enable paranoid mode

Risk Information

Risk Factor: Medium

CVSS Score Source: CVE-2016-4957

CVSS Score Rationale: Score from a more in depth analysis on vendor advisory

CVSS v2.0

Base Score: 5

Temporal Score: 3.7

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

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 8.6

Temporal Score: 7.5

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

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

Vulnerability Information

CPE: cpe:/a:ntp:ntp

Required KB Items: NTP/Running, Settings/ParanoidReport

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2016/06/02

Vulnerability Publication Date: 2016/06/02

Reference Information

CVE: CVE-2016-4953, CVE-2016-4954, CVE-2016-4955, CVE-2016-4956, CVE-2016-4957

BID: 91007, 91009, 91010

CERT: 321640