DDoS Attack Threats | DNS Flooder Attack Toolkit | Akamai Presentation

1
DNS Flooder A Reflection Toolkit

• Highlights from a Prolexic DDoS Threat Advisory

2
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

3
DNS Flooder v1.1 Toolkit Screenshot
4
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

5
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

6
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
7
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

8
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

9
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

10
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