Offensive pcap presented at BSidesLondon 2019

by Stuart Mcmurray,

Summary : When writing malware, oftentimes we need a bit more flexibility (i.e. sneakiness) than the victim's "normal" network stack provides us. Perhaps we'd like to not worry about our source address being identified or maybe we'd appreciate not having to fiddle with host-based firewalls. Enter libpcap. Aside from powering tcpdump, it enables us to send and receive all sorts of strange (and hopefully invisible) network traffic we can use on the offensive side of things.In this talk we'll first take a broad look at what libpcap is and what it can do for us, then we'll explore how to use it to do devious things like circumvent host-based firewalls, grab interesting info off the wire, ask system processes call us back with shells, and keep pesky EDR connections from happening. Source code for all of the techniques discussed in the talk will be made available.