NTP ntpd Mode 7 Error Response Packet Loop Remote DoS

This script is Copyright (C) 2009-2014 Tenable Network Security, Inc.


Synopsis :

The remote network time service has a denial of service
vulnerability.

Description :

The version of ntpd running on the remote host has a denial of
service vulnerability. It responds to mode 7 error packets with its
own mode 7 error packets. A remote attacker could exploit this by
sending a mode 7 error response with a spoofed IP header, setting the
source and destination IP addresses to the IP address of the target.
This would cause ntpd to respond to itself endlessly, consuming
excessive amounts of CPU, resulting in a denial of service.

See also :

https://bugs.ntp.org/show_bug.cgi?id=1331
http://www.nessus.org/u?3a07ed05

Solution :

Upgrade to NTP 4.2.4p8 / 4.2.6 or later.

Risk factor :

Medium / CVSS Base Score : 6.4
(CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:P)
CVSS Temporal Score : 5.6
(CVSS2#E:ND/RL:OF/RC:C)
Public Exploit Available : true

Family: Misc.

Nessus Plugin ID: 43156 ()

Bugtraq ID: 37255

CVE ID: CVE-2009-3563