Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
| From | Anonymous <nobody@mixmin.net> |
|---|---|
| Newsgroups | alt.hacker, alt.privacy.anon-server, comp.os.linux.advocacy, comp.sys.mac.system, alt.computer.security |
| Subject | Re: Socat vulnerability shows that crypto backdoors can be hard to spot |
| Date | 2016-02-28 02:18 +0000 |
| Organization | Mixmin |
| Message-ID | <natldo$g9$1@news.mixmin.net> (permalink) |
| References | (5 earlier) <n933d4$j9l$1@dont-email.me> <Z5Cdndw6QauMyCjLnZ2dnUU7-bOdnZ2d@earthlink.com> <n93n7k$h66$1@dont-email.me> <hPudndhhluxeHyjLnZ2dnUU7-cednZ2d@earthlink.com> <n957e3$4nq$1@dont-email.me> |
Cross-posted to 5 groups.
William Unruh: > On 2016-02-06, Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> wrote: >> On 02/05/16 18:53, William Unruh so wittily quipped: >>> On 2016-02-06, Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> wrote: >>>> On 02/05/16 13:15, William Unruh so wittily quipped: >>>>> On 2016-02-05, Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> wrote: >>>>>> On 02/04/16 18:51, William Unruh so wittily quipped: >>>>>>> On 2016-02-04, Anonymous <anonymous@foto.nl1.torservers.net> wrote: >>>>>>>> In article <n9018u$ufq$1@dont-email.me> >>>>>>>> William Unruh <unruh@invalid.ca> wrote: >>>>>>>>> >>>>>>>>> On 2016-02-04, Anonymous <anonymous@foto.nl1.torservers.net> wrote: >>>>>>>>>> Developers of the Socat networking tool have fixed a >>>>>>>>>> cryptographic flaw that left communications open to >>>>>>>>>> eavesdropping for over a year. The error is so serious that >>>>>>>>>> members of the security community believe it could be an >>>>>>>>>> intentional backdoor. >>>>>>>>>> >>>>>>>>>> http://www.csoonline.com/article/3029369/security/socat- >>>>>>>>>> vulnerability-shows-that-crypto-backdoors-can-be-hard-to- >>>>>>>>>> spot.html?google_editors_picks=true >>>>>>>>>> >>>>>>>>> >>>>>>>>> It contains a stupid statement. "Checking whether a 1024-bit number is >>>>>>>>> prime is doable, but is not exactly straightforward." It is very >>>>>>>>> straightforward, and very doable (RSA key generation does 10s to 100s in a >>>>>>>>> very short time.) While probabilistic even deterministic checking is not >>>>>>>>> that hard. Certainly the lesson is that a long term key should be >>>>>>>>> checked by someone other than the proposer. >>>>>>>> >>>>>>>> Couldn't you just fix this yourself by generating a new key and >>>>>>>> using it? >>>>>>> >>>>>>> Both sides need to use the same prime. In this case I guess they insist >>>>>>> on both using their "prime" (which is public knowledge). But their prime >>>>>>> was not prime meaning that deriving g^ab from g^a and g^b (all mod p, the >>>>>>> so called prime) became easier. Ie, no they want you to use theirs. >>>>>>> >>>>>>>> >>>>>>>>> I did not even know that DH would work with a non-prime key. RSA I >>>>>>>>> believe would fall over if you used a non-prime key. >>>>>>> >>>>>>> I guess it does work. All you use p for is to generate a key which you >>>>>>> can use in some other program (eg AES). >>>>>>> >>>>>>> In RSA you actually use the primes to encrypt, and if they are not >>>>>>> primes, there is a chance (how big?) that the decryption of the >>>>>>> encryption will not give the original message. >>>>>> >>>>>> I suspect it's actually simpler than that - multiple key solutions for >>>>>> non-prime [hence, non-secure] >>>>>> >>>>>> >>>>> >>>>> Depends on how hard it is to find one of those solutions. If it for >>>>> example only takes half the work to find one of two vs the time to find >>>>> a unique one, that is hardly less secure. If there are or order e^p more >>>>> solutions, then it would of course be trivial. But it is certainly >>>>> somewhere in between. Does it depend on the size of the largest factor? >>>>> the smallest factor? Ie, knowing g^a and g^b (mod p) how mush easier is >>>>> it to find g^ab (mod p) if p is composite than if it is prime? >>>>> >>>>>> >>>> >>>> yeah, some people that like mathematics for the sake of mathematics >>>> might want to derive that. Me, I just think in practical terms: if it >>>> takes half as many bots or half as many [stolen] cloudy threads to crack >>>> my key, or it's done in HALF the time because multiple solutions exist >>>> [due to use of non-prime], I think I'll take the extra few bits and use >>>> primes... >>>> >>> Since the time might be a billion times the age of the universe, that >>> this would be half a billion times the age of the universe, your >>> position would be silly if that is what you based it on. After all >>> simply using two computers instead of one, also halves the time. >>> Now I would strongly urge you to use a prime, and I suspect that the >>> reduction in time is much more than a factor of 2. But it would be >>> intellectually interesting to know how much. >> >> well, considering how keys though "uncrackable" as little as 10 years >> ago are now crackable using cloud services or distributed nodes of some >> kind, sometimes in 'real time' enough to be useful. anyway, never hurts >> to make it as secure as possible [and that's the point]. > > No, that is never the point. to make it as secure as possible disconnect > your computer from all networks remove any wireless/bluetooth/... > devices, and install it in a concrete and copper lined room. Oh, you > want to do something else with it or do not have the money? But you said > the whole point was "make it as secure as possible". Security does not exist in a vacuum, idiot. It is not an absolute condition existing separately from the environment in which you assess it. An isolated system cannot be called secure or insecure because security is a measure of how well a condition can be maintained relative to the risks in would incur from vulnerability to environmental processes. This is why we can say that one workstation is more secure than another one while both exist in the same environment. Once you remove both from enfironmental influences, both maintain their conditions relative to each other. The concept of security entails a realization of being secure from what. When conditions change, security changes, but security does not exist in the absense of change.
Back to alt.hacker | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <anonymous@foto.nl1.torservers.net> - 2016-02-04 02:16 -0500
Re: Socat vulnerability shows that crypto backdoors can be hard to spot William Unruh <unruh@invalid.ca> - 2016-02-04 17:20 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <anonymous@foto.nl1.torservers.net> - 2016-02-04 16:54 -0500
Re: Socat vulnerability shows that crypto backdoors can be hard to spot William Unruh <unruh@invalid.ca> - 2016-02-05 02:51 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> - 2016-02-05 11:17 -0800
Re: Socat vulnerability shows that crypto backdoors can be hard to spot William Unruh <unruh@invalid.ca> - 2016-02-05 21:15 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> - 2016-02-05 18:07 -0800
Re: Socat vulnerability shows that crypto backdoors can be hard to spot William Unruh <unruh@invalid.ca> - 2016-02-06 02:53 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Big Bad Bob <BigBadBob-at-mrp3-dot-com@testing.local> - 2016-02-05 21:22 -0800
Re: Socat vulnerability shows that crypto backdoors can be hard to spot William Unruh <unruh@invalid.ca> - 2016-02-06 16:36 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Nathan Hale <nobody@remailer.org.uk> - 2016-02-07 07:28 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <nobody@mixmin.net> - 2016-02-28 02:18 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <anonymous@foto.nl1.torservers.net> - 2016-02-27 23:27 -0500
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <nobody@mixmin.net> - 2016-03-01 04:42 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Anonymous <nobody@mixmin.net> - 2016-02-24 21:47 +0000
Re: Socat vulnerability shows that crypto backdoors can be hard to spot Nathan Hale <nobody@remailer.org.uk> - 2016-02-25 06:40 +0000
csiph-web