This new toolkit enables malicious actors to purchase, set up and use their own DNS servers to launch reflection attacks without the need to find open and vulnerable DNS servers on the Internet. This expedites the availability of the DNS botnet, enabling malicious actors to launch large cyber attacks without having to spend considerable time and resources building an army of bots through malware infections.
“As the DNS Flooder toolkit uses reflection and amplification techniques, attackers can anonymously launch powerful DDoS attacks with just a handful of servers,” said Stuart Scholly, president of Prolexic. “Widespread usage in the DDoS-as-a-Service market is likely and the security community needs to be aware and closely monitor this emerging threat.”
Prolexic has observed the DNS Flooder toolkit in multiple DDoS attack campaigns against its global client base over the last six months. In some cases, the campaigns have had amplification factors of 50 times the originating bandwidth.
The DNS Flooder toolkit uses a multi-step process to launch DDoS attacks:
- The toolkit spoofs the IP address of the intended target and creates a DNS request, which is sent to attacker’s DNS botnet.
- The attacker’s DNS botnet sends an extended DNS (EDNS) response back. The EDNS response includes more data than the DNS request (amplification). Because the IP address used in the request was spoofed, the response is reflected back to the attacker’s target.
- The toolkit loops multiple times, reflecting and amplifying the response to the target with each loop.