A short listing of research papers I’ve read or plan to read that use passive DNS (PDNS) data and graph analytics for identifying malicious domains.
Host domain graphs are bipartite graphs mapping hosts/IPs to domains that they either resolved (passive DNS) or visited (web proxy logs). These graphs are used heavily in operational security machine learning papers on network threat hunting as they provide insight into the behavioral patterns across an enterprise or ISP.
This is the Definitive Security Data Science and Machine Learning Guide. It includes books, tutorials, presentations, blog posts, and research papers about solving security problems using data science.
Throughout this research, I came across several security related academic and professional research papers on security topics that use Deep Learning as part of their research. What follows is a list of the papers/slides/videos that I found, and these may be useful to others. If you have others that you think should be added to this list, please ping me: @jason_trost.
In a previous post, I discussed some of my experiences with heralding, a credential grabbing honeypot. In this post, I will briefly analyze a sample I obtained from tftp’ing a sample based on heralding log entries. This sample appears to be targetted at MIPS based systems installs that use very weak default creds (root:5up, Admin:5up). There are a few devices that I could find that uses these creds. There are likely many more.
In my previous post I mentioned that I was not able to download a sample from the tftp commands. Well today, I was finally able to download one of the samples via tftp without it timing out.
According to 3 AVs on Virustotal, 3f3863996071b4f32ca8f8e1bfe27a45 is Mirai, BUT the IPs performing the telnet scans only attempted 2 username/password combinations (and the Mirai source code uses many more so this may be a new variant or something completely different).
Here are the IPs observed trying to get my honeypot to download and execute this specific sample (via “tftp -l 7up -r 7up -g 126.96.36.199”).
Switch back to the tcpdump terminal, and kill it. Also, and this is very important, kill the “qemu-mips 7up” processes. The 7up sample immediately starts scanning port 23 at a high rate so you don’t want it running very long.
As you can see from the pcap, we were able to extracted a couple of IOCs:
Privacy protected so kind of a dead end.
Not privacy protected and linked with some Mirai activity (see below). Also of note is the Registrant City which is “fastflux”, kind of funny.
Searching for the registrant email, dlinchkravitz[@]gmail[.]com, turns up these blog posts: