It’s early June 2025, we are preparing our C2 infrastructure and payload for an upcoming red team engagement. We know the client, we also know some aspects of their infrastructure because we do a lot of regular pentests for them throughout the year. We don’t need to worry about the social engineering part because it was agreed to do the tests in an “assume breach” scenario and we’ll thus have a contact on site who will download, open or execute whatever we ask them to. So, the objective is simple, we have approximately 2 months to get an initial foothold on the network and do some post-exploitation.
We can’t say that we felt highly confident, but we had a comfortable margin for error, and we knew that we could go back to the drawing board in case something did not work as intended. Little did we know that we had greatly underestimated the difficulty of the task, and that a key part of their infrastructure would end up completely ruining our plans. We were not quite prepared for what lied ahead of us.
Continue reading From a Regular Red Team Exercise to Developing a Custom C2 Channel over MS Teams
