Daniel Kopp

Daniel Kopp, Eric Strehle, Oliver Hohlfeld

In September 2019, 600 armed German cops seized the physical premise of a Bulletproof Hoster (BPH) referred to as CyberBunker 2.0. The hoster resided in a decommissioned NATO bunker and advertised to host everything but child porn and anything related to terrorism while keeping servers online no matter what. While the anatomy, economics and interconnection-level characteristics of BPHs are studied, their traffic characteristics are unknown. In this poster, we present the first analysis of domains, web pages, and traffic captured at a major tier-1 ISP and a large IXP at the time when the CyberBunker was in operation. Our study sheds light on traffic characteristics of a BPH in operation. We show that a traditional BGP-based BPH identification approach cannot detect the CyberBunker, but find characteristics from a domain and traffic perspective that can add to future identification approaches.

Daniel Kopp, Christoph Dietzel, Oliver Hohlfeld

DDoS attacks remain a major security threat to the continuous operation of Internet edge infrastructures, web services, and cloud platforms. While a large body of research focuses on DDoS detection and protection, to date we ultimately failed to eradicate DDoS altogether. Yet, the landscape of DDoS attack mechanisms is even evolving, demanding an updated perspective on DDoS attacks in the wild. In this paper, we identify up to 2608 DDoS amplification attacks at a single day by analyzing multiple Tbps of traffic flows at a major IXP with a rich ecosystem of different networks. We observe the prevalence of well-known amplification attack protocols (e.g., NTP, CLDAP), which should no longer exist given the established mitigation strategies. Nevertheless, they pose the largest fraction on DDoS amplification attacks within our observation and we witness the emergence of DDoS attacks using recently discovered amplification protocols (e.g., OpenVPN, ARMS, Ubiquity Discovery Protocol). By analyzing the impact of DDoS on core Internet infrastructure, we show that DDoS can overload backbone-capacity and that filtering approaches in prior work omit 97% of the attack traffic.