LinuxFest Northwest 2019: Ghostbusting
Channel: linuxfestnorthwest
Date: 30/04/2019

Presented by Seth David Schoen 

With the political conflict over encryption back in full swing, governments of several countries are pushing the idea that developers of communications apps should have to modify them, on government request, to include backdoors or various ways of getting around encryption. This poses a disturbing challenge for free software developers.

One recent suggestion from the British government calls for making developers support a "ghost user" who can join your encrypted conversations invisibly. While proponents argued that this would require only the most minimal of software changes, we were skeptical of how undetectable the ghost would really be. We've been exploring this question with a few reverse engineering tools and we think that the likeliest answer is that the most straightforward forms of the ghost concept may be quite detectable indeed.

I'll discuss the history and status of this issue, and a few ways that we think reverse engineering tools undermine the governments' suggestions.