Biblio

Web security is a big concern in the current Internet; users may visit websites that automatically download malicious codes for leaking user's privacy information, or even mildly their web browser may help for someone's cryptomining. In this paper, we analyze abusive web resources (i.e. malicious resources and cryptomining) crawled from the Alexa Top 150,000 sites. We highlight the abusive web resources on Alexa ranking, TLD usage, website geolocation, and domain lifetime. Our results show that abusive resources are spread in the Alexa ranking, websites particularly generic Top Level Domain (TLD) and their recently registered domains. In addition, websites with malicious resources are mainly located in China while cryptomining is located in USA. We further evaluate possible counter-measures against abusive web resources. We observe that ad or privacy block lists are ineffective to block against malicious resources while coin-blocking lists are powerful enough to mitigate in-browser cryptomining. Our observations shed light on a little studied, yet important, aspect of abusive resources, and can help increase user awareness about the malicious resources and drive-by mining on web browsers.

Botnets are accountable for numerous cybersecurity threats. A lot of efforts have been dedicated to botnet intelligence, but botnets versatility and rapid adaptation make them particularly difficult to outwit. Prompt countermeasures require effective tools to monitor the evolution of botnets. Therefore, in this paper we analyze 5 months of traffic from different botnet families, and propose an unsupervised clustering technique to identify the different roles assigned to C&C servers. This technique allows us to classify servers with similar behavior and effectively identify bots contacting several servers. We also present a temporal analysis method that uncovers synchronously activated servers. Our results characterize 6 C&C server roles that are common to various botnet families. In the monitored traffic we found that servers are usually involved in a specific role, and we observed a significant number of C&C servers scanning the Internet.