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Group Chat Vulnerability Discovered in Cryptocat, Project Fixes and Apologizes
alphadogg writes "The founder of an eavesdropping-resistant instant messaging application called Cryptocat has apologized over a now-fixed bug that made some types of messages more vulnerable to snooping. Cryptocat, which runs inside a web browser, is an open-source application intended to provide users with a high degree of security by using encryption to scramble messages. But Cryptocat warns that users should still be very cautious with communications and not to trust their life with the application. The vulnerability affected group chats and not private conversations. The encryption keys used to encode those conversations were too short, which in theory made it easier for an attacker to decrypt and read conversations."
The bug report/merge request, and an analysis of the bug (although, in light of the Cryptocat's gracious response, overly acerbic and dismissive of the project).
Why not just use OTR with pidgin? Supports any protocol you'd care to mention.
This bug and the history of it point to the cryptocat people being utterly incompetent. It's perfectly possible that they did what they did with the best of intentions and that they reacted as well as they could - that does not change one iota about them being incompetent and that you better don't trust the work of incompetent engineers. It's nice that that civil engineer did not intend to kill anyone and that she helped in rescuing people, but still her incompetence is what caused the bridge to collapse and what makes it reasonable to be suspicious of the other bridges she's responsible for.
Does anyone know what happened to the HTML5 (non-plugin) based server-side version of cryptocat?
I don't care if it's less secure than the new plugin-required version.. it will still probably defend against an eavesdropper in my college dorm or at Starbucks.
How many more years will slashdot have an off-by-one error on your Score in your profile?
The really ugly 'gotcha', with any attempt at encrypted/obfuscated/steganographic communication, cryptocat included but hardly alone, is storage.
If your adversary is just drinking from the firehose, and lacks the ability to do more than a cursory inspection, all you have to do is be better than their cryptoanalysts today. If they have sufficient storage to archive a nontrivial percentage of what passes by(or their cursory inspection is good enough to classify suspicious encrypted traffic for storage) you have to be better, today, than their cryptoanalysts for however long what you are saying is relevant. The former is hard, the latter is downright scary.
It's encrypted end to end and you can totally discuss your plans and share secrets using the instant messaging. For better protection, why not wrap them in a PDF labelled 'secret plans NSA do not read"?
Plus its from a trusted company that never harms their customers, Microsoft, in a country with strong privacy laws, America. So its double plus good private!
I don't really want to live in a world where I have to actively hide shit from people or they'll try to take advantage of me
Neither do I, but such is the world we live in. All you can do is accept that the world is a mostly shitty place, deeply appreciate the moments of stunning beauty it offers as well and try to improve your little corner of it.
Societies are composed of many different kinds of individuals, and each individual can behave in many different ways. You need to protect yourself even if just a small percentage of people in society want to harm you some of the time.
Bullshit. We're biological beings subject to natural laws. A society in which everybody cooperates is provably not a stable solution, nor, for that matter, is it a very good solution. Yes, that's a mathematical fact.
The percentage of people wanting to harm you today is remarkably small by historical standards, and the amount of protection you need is small. Be happy about that, and then take some reasonable precautions, like everybody else.
> I don't really want to live in a world where I have to actively hide shit from people or they'll try to take advantage of me. Lack of privacy is a social problem soluble by bringing up people with a better attitude toward their fellow man, not a technical one soluble with an arms race (which you will lose, btw).
Goodness, you are an optimist. The military, economic, or social advantage to accessing private communications is very large, and the social and economic and political advantages are _tremendous_. Education won't solve that: the first person in the "educated" world who starts copying test answers, or reading their boss's private correspondence, will have tremendous advantages socially and in the workplace. That's part of what the NSA was doing to EU communications: industrial espionage to benefit American companies.
The last sentence of this article says it all :
Also I learned that it means nothing when I hear "it is open source and peer reviewed".
Cloudflare is better at protecting my server infrastructure than TOR is.
Change is certain; progress is not obligatory.
The mistakes made are utter beginner's mistakes that nobody even halfway competent with regard to cryptography would make. The only other possibility is that these mistakes were made intentionally.
While it is unclear whether utter cluelessness or devious intent is to blame, this software should not be trusted on any level or for any purpose. Of the people writing it can make this kind of mistake, then there will likely be a number of other mistakes in it that affect security and this piece of trash should be regarded as broken for any purpose.
Doing crypto is not a beginner's game. There are countless ways to get it wrong, and most of them cannot be found by testing, but require in-depth understanding and meticulous analysis of the mechanisms used. And encryption software being OSS only helps if some people with a clue care to review it.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
You gain competence the same way pilots do. They don't get to fly hundreds-of-passengers boeings on their first day either. It's OK to be a crypto beginner. But why do they publish a chat system instead of scribbling around in Cryptool?
If you see someone looking into a loaded shotgun barrel with their finger on the trigger, you don't say "oh, let him learn by trial and error". You take the gun from him, slap him across the face and send him learning the basics.
Of course it runs NetBSD. BTC: 1NT7QvbetmANwaMzhpVL6
You gain competence by studying it, but trying things, etc. Before that you already have to be a pretty good and experienced programmer. People without that skill should not even try, it is a mandatory skill. You cannot learn how to program well doing crypto, crypto has a whole additional set of difficult and subtle requirements.
And no, test-and-fix does not work for crypto. That is not "my rule", but in the very nature of things. The problem is that testing will not show the mistakes for crypto, and hence it is not the "normal" process at all.
All pretty obvious to anybody that actually cares to find out. Your cluelessness is a disgrace.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.