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About tor: if an attacker produces a public key that collides with the SHA-1 hash of someone else's hidden service, then he would still need to generate the corresponding RSA-1024 private key, which is infeasible as of today. Is this correct?
Earlier quoted context omitted.
Create 2 torrents with the same hash. Release one into the wild. Wait. Infect.
This requires the addition of random garbage in the first file which someone will detect anyway. Why not release an infected file with a timebomb malware instead of colliding SHA1? Much cheaper. Still, none of this allows you to attack an already existing torrent.
One practical attack using this: create a torrent of some highly desirable content- the latest hot TV show in high def or whatever. Make two copies, one that is malware free, another that isn't. Release the clean one and let it spread for a day or two. Then join the torrent, but spread the malware-hosting version. Checksums would all check out, other users would be reporting that it's the real thing, but now you've g…
How am I going to explain this to my wife? Actually a serious question. How do we communicate something like this to the general public?
Torrent poisoning is the most ripe for exploitation and the one with the highest return for a malicious attacker.
So when you talk to someone who torrents, just tell them that the way the torrents verify a file is the correct one is no longer secure, and they have to keep an eye out for the next software update. And if anyone is paranoid, then stop downloading new torrent files, although there is no problem with seeding.
Now that I think about it, I think it is crucial for everyone to keep seeding as much as they can, because it reduces the probability of a bad torrent chunk from spreading as much across the network.
EDIT: Here's a good article that isn't very technical
https://www.wired.com/2017/02/common-cryptographic-tool-turn...
One practical attack using this: create a torrent of some highly desirable content- the latest hot TV show in high def or whatever. Make two copies, one that is malware free, another that isn't. Release the clean one and let it spread for a day or two. Then join the torrent, but spread the malware-hosting version. Checksums would all check out, other users would be reporting that it's the real thing, but now you've g…
Malware in a video? Is that possible? How does it work?
One practical attack using this: create a torrent of some highly desirable content- the latest hot TV show in high def or whatever. Make two copies, one that is malware free, another that isn't. Release the clean one and let it spread for a day or two. Then join the torrent, but spread the malware-hosting version. Checksums would all check out, other users would be reporting that it's the real thing, but now you've g…
this isn't quite true, bittorrent have checksums for each piece in the torrent, I not saying its impossible to do but its significantly harder than just finding 2 files with the same hash.
One practical attack using this: create a torrent of some highly desirable content- the latest hot TV show in high def or whatever. Make two copies, one that is malware free, another that isn't. Release the clean one and let it spread for a day or two. Then join the torrent, but spread the malware-hosting version. Checksums would all check out, other users would be reporting that it's the real thing, but now you've g…
ie: I'd be downloading (and putting together) some blocks of the "real" movie and some blocks of the "malware". I'm guessing the resultant file wouldn't even open?
> "10 years after of SHA-1 was first introduced" wasn't SHA-1 introduced in the 90's?
Here's a good blog about how SHA-1 works: http://www.metamorphosite.com/one-way-hash-encryption-sha1-d... . The biggest risk I see with this is how torrents are affected: https://en.wikipedia.org/wiki/Torrent_poisoning There's also a problem with git, but I don't see it being that as susceptible as torrents: http://stackoverflow.com/a/34599081/6448137
What about git? This makes it technically possible to get a backdoored linux repo with the same commit hash. EDIT: this is wrong, it's not a second pre-image attack only a collision attack. That is, you can create 2 git repositories with the same commit hash, but not a git repo that matches an already existing repo. In other words, you can create 2 things with the same hash, but can't control what that hash actually…
One practical attack using this: create a torrent of some highly desirable content- the latest hot TV show in high def or whatever. Make two copies, one that is malware free, another that isn't. Release the clean one and let it spread for a day or two. Then join the torrent, but spread the malware-hosting version. Checksums would all check out, other users would be reporting that it's the real thing, but now you've g…
Since it takes 6,500 CPU years and 110 GPU years, it won't quite be the latest show, unless you have really deep pockets.
There are way less costly ways to make money illegally using simpler vulnerabilities or by being a pay-to-use DDoS provider.