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Old 2017-09-23, 10:59   #45
crack11
 
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dear sir if you don t mind can you pm your skype id than i give you more exmpel..
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Old 2017-09-23, 13:26   #46
Dr Sardonicus
 
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Curiously, the OP's original question was posted to a Wolfram Stackexchange chat room the day before it was posted to this august Forum.

The user zhk had identified the trouble as an overflow problem.

I also found an old thread in this Forum with exactly the same kind of calculation as in this one. Major difference: When asked, the OP in that thread described precisely what he was trying to do and why: It's possible to calculate an unknown RSA modulus?
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Old 2017-09-23, 13:43   #47
crack11
 
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yes DR sir my calculating string same like this:http://www.mersenneforum.org/showthread.php?t=13524
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Old 2017-09-23, 14:36   #48
R. Gerbicz
 
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Quote:
Originally Posted by axn View Post
It looks to me, from the numbers posted above, that they know the plaintext/ciphertext pairs, but doesn't know the N, and the gcd is supposed to give the N? Weird.
Yes, exactly that!
Code:
m1^e==c1 mod N  [1]
m2^e==c2 mod N  [2]
from here: N | gcd(Z1,Z2)=gcd(m1^e-c1,m2^e-c2), because N|Z1,Z2, but it is NOT TRUE, that gcd(Z1,Z2)=N. But since for random numbers gcd is "small", the gcd(Z1,Z2) will be a small multiple of N, hence you (not me) can "easily" factor that, and using [1] or [2] we can easily choose the true value of N (in almost every cases) as a divisor of gcd(Z1,Z2). The first hard step is to get gcd(Z1,Z2).

And why would anybody solve this problem where the original message is KNOWN , these are m1 and m2. Or there are other c values, where m is unknown.
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Old 2017-09-23, 15:00   #49
Dr Sardonicus
 
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We've repeatedly told the OP "The numbers are too big"


Repeatedly ignored.
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Old 2017-09-23, 16:25   #50
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Could it be done by calculating everything mod some suitable prime larger than N, eg 2^521-1 (assuming N is RSA512)? Or mod several smaller primes and applying the Chinese Remainder Theorem to recover N?

Chris
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Old 2017-09-25, 13:15   #51
crack11
 
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Dear all.

my string same like this N modul recover..
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Old 2017-09-25, 13:20   #52
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Quote:
Originally Posted by crack11 View Post
Dear all.

my string same like this N modul recover..
there are very basic results you could get if you tried. but since you don't seem to know about PARI/GP etc. odds are you don't know what my comment means.
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Old 2020-08-13, 04:15   #53
crack11
 
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no body try to solve this issu overflow?
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Old 2020-08-13, 06:50   #54
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Quote:
Originally Posted by crack11 View Post
no body try to solve this issu overflow?
Arbitrary precision arithmetic is a solved problem.
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Old 2020-08-13, 10:45   #55
crack11
 
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dear sir,


your send link not solve the probleam



its all ready solve like old exp-65537 5 digt


but new exp-12 digit



can it possibel with exp calculating start?
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