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4096 RSA key in the strongset factored?
71–80 of 114 posts
Re: 4096 RSA key in the strongset factored?
#72Earlier quoted context omitted.
RSA is not broken per se. (AFAIK) If you have a 4096-bit key, nobody is able to factor a 4096-number yet . However, using a bad random prime generator might lead to birthday attack when someone is using the same prime as you. Having two keys that share a prime, it is possible to factor both . Also, one of the "primes" used is 231, which is extremely stupid, its factors 3 7 11, so there are two keys that are using the…
Wouldn't RSA just fail if you used a non-prime factor? You shouldn't be able to decrypt any messages if you calculate the totient incorrectly, and for a public key pq, if either p or q isn't prime then (p-1)(q-1) won't be the totient.
Re: 4096 RSA key in the strongset factored?
#73The issue with this is that gpg doesnt check these keys when you sign them (presumably because speed)
So even if you verify the persons identity correctly when you sign their key you can't tell if the key is garbage easily.
In fact i guess it doesn't matter much if the other person communicating with you is fooling you amd forwarding all the things he receives to the nsa/whay not regardless ;)
Re: 4096 RSA key in the strongset factored?
#74I'm almost certain this news is wrong. I know that because I made the same mistake a while ago. Luckily for me I didn't publish it, but I already had written mails to a number of people (including hpa) warning them of a compromised key (which was a false alarm). Here's what's going on: There are a number of keys on the keyservers that are faulty copies of real keys - they share most of the values, but have some error…
It remains to be seen whether 'These keys don't really do any harm.'
And good job repeating my research without any acknowledgment. Does your sponsor know about Phuctor? What if he were to read this thread?
Re: 4096 RSA key in the strongset factored?
#75Earlier quoted context omitted.
Should . Obviously something went very wrong and the "primes" weren't properly checked to actually be primes.
Well, obviously something went wrong. But the way I understand it RSA shouldn't work at all if you used a composite factor, decrypting a message will just give a wrong result. Unless, by some incredible fluke, they managed to find a carmichael number.
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Re: 4096 RSA key in the strongset factored?
#76Earlier quoted context omitted.
It is actually a pure factorization of two separate keys. But subsequent evidence in this conversation (from agwa above) makes me think that they aren't valid keys that are actively being used by the people in question, but rather spurious additional data being returned by keyservers for some reason, that probably wouldn't be accepted as valid by gpg.
I don't understand this well enough to know what an accurate title should say. Can you or anyone suggest one?
The title should accurately represent the article, even if it turns out the article is wrong; anything else would be editorializing. So even if it turns out the factored subkeys are phony, this article doesn't say that, so neither should the title. The top two comments provide a useful correction.
So, the current title seems fine. If anything, the question mark is a bit of editorialism.
Re: 4096 RSA key in the strongset factored?
#77Earlier quoted context omitted.
RSA is not broken per se. (AFAIK) If you have a 4096-bit key, nobody is able to factor a 4096-number yet . However, using a bad random prime generator might lead to birthday attack when someone is using the same prime as you. Having two keys that share a prime, it is possible to factor both . Also, one of the "primes" used is 231, which is extremely stupid, its factors 3 7 11, so there are two keys that are using the…
Wouldn't RSA just fail if you used a non-prime factor? You shouldn't be able to decrypt any messages if you calculate the totient incorrectly, and for a public key pq, if either p or q isn't prime then (p-1)(q-1) won't be the totient.
I've always wondered about this.
Wikipedia says ( http://en.wikipedia.org/wiki/RSA_(cryptosystem) ): "When m is not relatively prime to n, the argument just given is invalid. This is highly improbable (only a proportion of 1/p + 1/q − 1/(pq) numbers have this property), but even in this case the desired congruence is still true. Either m ≡ 0 (mod p) or m ≡ 0 (mod q), and these cases can be treated using the previous proof.".
I'm not sure I follow 100% - perhaps someone smarter can explain.
Re: 4096 RSA key in the strongset factored?
#78Earlier quoted context omitted.
Wouldn't RSA just fail if you used a non-prime factor? You shouldn't be able to decrypt any messages if you calculate the totient incorrectly, and for a public key pq, if either p or q isn't prime then (p-1)(q-1) won't be the totient.
http://en.m.wikipedia.org/wiki/Carmichael_number
I suppose that would work, although with a factor of 3 more than 1/3 of all inputs are not relatively prime so in those cases it would fail anyway.
Re: 4096 RSA key in the strongset factored?
#79Earlier quoted context omitted.
I don't understand this well enough to know what an accurate title should say. Can you or anyone suggest one?
The title should accurately represent the article, even if it turns out the article is wrong; anything else would be editorializing. So even if it turns out the factored subkeys are phony, this article doesn't say that, so neither should the title. The top two comments provide a useful correction. So, the current title seems fine. If anything, the question mark is a bit of editorialism.
The HN guidelines (and longstanding practice) are to prefer the article's title unless it is misleading or linkbait. A false title is misleading.
We sometimes add a question mark when a title is disputed but it isn't clear what a good (i.e. accurate and neutral) title would be. That's the best I've got until someone suggests an accurate and neutral title.
Re: 4096 RSA key in the strongset factored?
#80I was extremely surprised to see the source of this at the top of HN, as I am familiar with this web site and its operator from an an extremely toxic online forum, which I won't mention or elaborate on. I am careful not to share negative remarks, but I will firmly state that I believe that this:
>Consequently, the originally intended, civilised process of emailing the victim, keeping things quiet for a while to give them time to update and so on is not practicable.
Strikes me as disingenuous coming from this source.