3 ms·
Making a total hash of it
- aston 19y agoI can't believe it's 2008 and we're still reading new stories about MD5 collision-resistance. We get it, anybody can manufacture N files with the same hash and different content. Don't use MD5 as a piece of your vote commitment scheme and move on. All of this was news years ago. edit: MD5 is still good for random other stuff. If you MD5 something, it's not that easy for someone to find a collision with it. I'm anxiously awaiting the revelatory article on rainbow tables in The Economist.
- tptacek 19y agoWhat is MD5 good for? It's slower than a CRC and less secure than SHA1. It's a crappy universal hash (bad constant factors) and it's usually much too large for a unique identifier.
- aston 19y agoMy intent isn't to bat for MD5, really. But since you asked me, I'll point out that MD5 is actually not that bad if you want a deterministic string of randomly distributed bits. If you don't need all 128 bits, nobody's forcing you to keep the extra ones. That said, you might as well use SHA1.
- tptacek 19y agoFor what it's worth, almost any random number generator is better than MD5 at giving a deterministic random bit string, given a seed. You might start with OpenBSD arc4random.
- mattmaroon 19y agoYou have to give them credit for explaining it well to non-hackers.
- mechanical_fish 19y agoAn article which explains that a lock is broken, but doesn't tell you what the lock is protecting, how to get it changed, and what alternative locks are available, is not explaining the situation well.
- tptacek 19y agoAnd, of course, this is old news, and, of course, it only works with MD5 (and --- we expect, but do not yet know --- SHA1, but not SHA256). Your takeaway from this article is, "don't ever use MD5 again". It has no value. Use CRC's for error detection, and use a SHA hash for security.
- mattmaroon 19y agoThis is probably not old news to most readers of The Economist.
- tptacek 19y agoIt's also not useful to most readers of The Economist, since nothing they commonly use relies on MD5.
- mattmaroon 19y agoThe Economist is basically general interest stuff for smart people. They seem to like that sort of thing.
- davidw 19y agoYeah, there is a bunch of news there that's not personally that relevant to me, but I like reading it just the same, being a bit of an information junkie.
- mechanical_fish 19y agoYeah, my first move on seeing this article was to scan it for mention of the fact that there are other hash algorithms than MD5 which still work perfectly well. I don't think this article would be bad if it had a second page that went on to provide some perspective. As it stands, it reads as a general indictment of all of computer security. They claim that the methods are secure, but they're really not! Don't trust those computer guys, because the One True Algorithm has a hole!