On Sun, Mar 19, 2017 at 06:14:22PM +0100, Norbert Bollow wrote: > That is true, if the attacker already knows whose communications they > want to snoop on. However one of the main benefit of using encrypted > communications is in the area of making it much more expensive and > politically risky for the attacker to determine which targets have > value.
The attacker (for many values of "attacker") is and will be particularly interested in communications that are encrypted -- because they'll stand out. Granted, this will diminish as more communications become encrypted, but for the forseeable future, anyone using encryption or similar privacy measures will be targeted: https://www.wired.com/2014/07/nsa-targets-users-of-privacy-services/ I agree with you that encryption makes it more expensive, and that's an argument for deploying it, but I don't agree that it's politically risky: there are no appreciable consequences for anyone engaging in this. Even at the commercial level (e.g., Verizon's insertion of unblockable cookies in order to conduct surveillance) there are no appreciable consequences for any violation of user privacy or security -- merely inconsequential slap-on-the-wrist fines and then it's right back to business as usual. > In the absence of encryption, that can be achieved by means of mass > surveillance anywhere between the communications endpoints followed by > (possibly AI-based) pattern analysis, at near-zero incremental cost and > near-zero incremental risk per additional group that is subjected to > such surveillance for reasons of its communications being possibly of > interest to the attacker. I almost entirely agree with you on this, but want to point out that if an attacker has compromised an endpoint, they can stop there: there's no need to worry about the rest. And endpoints are already compromised by the hundreds of millions, with more every day. (And as more endpoints become part of the IOT, the rate of compromise will increase drastically.) I think it's quite reasonable to extrapolate a billion compromised endpoints sometime in the next couple of years. (I also think that in a couple of years I'll shake my head at how much of an underestimate that turned out to be.) So if it becomes desirable or profitable for the new owners of those systems to pay specific attention to encrypted mailing list traffic, they will...and probably much quicker than anyone anticipates. They won't get it right the first or second time, just like they didn't get botnet C&C organization right the first or second time -- but it won't take them long to learn. Thus the target end user population for encrypted mailing lists looks something like this: Nobody using freemail providers -- these fall into two categories: those that are owned and those that are going to be owned. Nobody using webmail -- webmail implementations have a long and sad history of serious security issues. And "browser security" is often an oxymoron. Nobody using Windows, MacOS, Android, or iOS. There are already too many exploits on the table to keep track of, and there can be no doubt that these are only a fraction of the total: many more are held by security researchers, vulnerability brokers, intelligence agencies, etc. And Linux probably should be added to that list in the near future, as its increasing deployment has clearly made it an attractive target. (Nod to the past week's releases by the Shadow Brokers, which are surely the tip of the tip of the iceberg.) Nobody with poor email habits, e.g., top-posters, full-quoters, people who use HTML markup. (Since these undercut encryption, sometimes rather badly.) Nobody using the IOT to send or receive email, e.g., their car, which was very likely pre-compromised at the factory. That doesn't leave a lot of people. I'm not saying "don't do it". As an intellectual exercise and a development challenge, it's interesting. I'm saying "make sure -- if people are thinking about deploying this -- that they understand that they have almost no chance of making this work as intended in the real world." ---rsk _______________________________________________ Mailman-Developers mailing list Mailman-Developers@python.org https://mail.python.org/mailman/listinfo/mailman-developers Mailman FAQ: http://wiki.list.org/x/AgA3 Searchable Archives: http://www.mail-archive.com/mailman-developers%40python.org/ Unsubscribe: https://mail.python.org/mailman/options/mailman-developers/archive%40jab.org Security Policy: http://wiki.list.org/x/QIA9