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Attackers Wage Network Time Protocol-Based DDoS Attacks
From: InfoSec News <alerts () infosecnews org>
Date: Tue, 31 Dec 2013 10:07:51 +0000 (UTC)
By Kelly Jackson Higgins
December 30, 2013
Attackers have begun exploiting an oft-forgotten network protocol in a new
spin on distributed denial-of-service (DDoS) attacks, as researchers
spotted a spike in so-called NTP reflection attacks this month.
The Network Time Protocol, or NTP, syncs time between machines on the
network, and runs over port 123 UDP. It's typically configured once by
network administrators and often is not updated, according to Symantec,
which discovered a major jump in attacks via the protocol over the past
"NTP is one of those set-it-and-forget-it protocols that is configured
once and most network administrators don't worry about it after that.
Unfortunately, that means it is also not a service that is upgraded often,
leaving it vulnerable to these reflection attacks," says Allan Liska, a
Symantec researcher in blog post last week.
Attackers appear to be employing NTP for DDoSing similar to the way DNS is
being abused in such attacks. They transmit small spoofed packets
requesting a large amount of data sent to the DDoS target's IP address.
According to Symantec, it's all about abusing the so-called "monlist"
command in an older version of NTP. Monlist returns a list of the last 600
hosts that have connected to the server. "For attackers the monlist query
is a great reconnaissance tool. For a localized NTP server it can help to
build a network profile. However, as a DDoS tool, it is even better
because a small query can redirect megabytes worth of traffic," Liska
explains in the post.
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- Attackers Wage Network Time Protocol-Based DDoS Attacks InfoSec News (Dec 31)