DDoS Attack Threats | DNS Flooder Attack Toolkit | Akamai Presentation

DNS Flooder: A Reflection Toolkit
Highlights from a Prolexic DDoS Threat Advisory
©2014 AKAMAI | FASTER FORWARD
TM
What is DNS Flooder?
• In mid-2013, the DNS Flooder Toolkit v1.1 was
leaked on popular hack forums
• The toolkit uses a new, popular method of crafting
large DNS resource records
• Malicious actors can amplify responses by a factor of
50 or more per DNS request, and may customize
their own DNS records, adding words and comments

©2014 AKAMAI | FASTER FORWARD
TM
DNS Flooder v1.1 Toolkit Screenshot
©2014 AKAMAI | FASTER FORWARD
TM
DNS Flooder: DDoS Attack Threat
• DNS Flooder is very popular
• The amplified nature of the attack means it only
needs a few servers to achieve a large DDoS flood
• Because of the reflection techniques DNS Flooder
uses, attackers are fully anonymous and the origin of
the attack is very difficult to pinpoint
• Several attacks have already been launched against
Akamai customers

©2014 AKAMAI | FASTER FORWARD
TM
Attack Overview
• One attack against an Akamai customer using the
DNS Flooder toolkit lasted approximately four hours
• Prior to the use of the tool, the attackers set up DNS
servers for their own use, building their own botnet
without the need for infection
• This method can also inject messages into the attack
payload

©2014 AKAMAI | FASTER FORWARD
TM
DDoS Flooder Attack Statistics
San Jose London Hong Kong Washington
Peak bits per second
(bps)
5.00 Gbps 80.00 Gbps 5.00 Gbps 20.00 Gbps
Peak packets per second
(pps)
400.00 Kpps 7.50 Mpps 400.00 Kpps 2.00 Mpps
Peak traffic values complied from Akamai scrubbing centers during a
DNS Flooder campaign
©2014 AKAMAI | FASTER FORWARD
TM
How Does DNS Flooder Work
• The toolkit uses a DNS reflection attack to
amplify DDoS bandwidth by a factor of 50 or
more
• The attacker sends a vulnerable DNS server
a DNS any resource record query
• The any resource record query returns all records of all types
stored on the server
• Can exceed 4,000 bytes
• By sending the request with a fake source
IP, the big any resource record is reflected to
the target

©2014 AKAMAI | FASTER FORWARD
TM
How DNS Flooder Works, cont.
• DNS Flooder crafts its IP header and DNS resource
header manually
• Requires root access on the attacking computer
• Allows nuances of DNS to be exploited to ensure
maximum possible response size
• Falsifying the IP address at the source makes the
original attack nearly untraceable – the requests are
totally anonymous
©2014 AKAMAI | FASTER FORWARD
TM
Threat Advisory: NTP – DNS Flooder toolkit
• Download the threat advisory, DNS Flooder v1.1
• This DDoS threat advisory includes:
•Indicators of the use of the DNS Flooder toolkit
•Analysis of the source code
•Example query created by the toolkit
•Sample payload
•Who is believed to be behind these attacks
•The SNORT rule and target mitigation using ACL entries
•Statistics and payloads from two observed DNS Flooder
campaigns against Akamai clients
•The full source code of DNS Flooder


©2014 AKAMAI | FASTER FORWARD
TM
About Prolexic (now part of Akamai)
• We have successfully stopped DDoS attacks for more
than a decade
• Our global DDoS mitigation network and 24/7 security
operations center (SOC) can stop even the largest
attacks that exceed the capabilities of other DDoS
mitigation service providers