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Alice has three cousins who are all named Bernard. So, to distinguish them, she calls them B1, B2 and B3.

They use the same RSA exponent e=5, but, of course, each has his own RSA modulus, N1, N2 and N3, respectively:

N1=100000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000267000000000000000000000000000000000000000000000062211

N2=10000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000008600000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000249

N3=100000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000144480000000000000000000000000000000000000000000012900000000000000000000000000000000000000000000000001847151

Alice encrypts the same message M with a naive RSA: she computes and sends:

  • C1 = M^e mod N1 to B1,
  • C2 = M^e mod N2 to B2,
  • C3 = M^e mod N3 to B3.

She sends:

C1=54441450659621670138360534471370800521600773045442281730224051211705532693187014199922098586090266741072718826771799691781401886564933014954223326535311841540432522142627309522600548951548447021571940

C2=8282782093189723788717845369100238776500872157054237851614694174668495656149977137631548578299377595431207979722346661247438567968974918897593524023383338024350662969736998086335077647380300428457694941

C3=46238842391593215363511659808823181832022817089432016337588942314252873360090772070653341532722441372601889625844930893539264001083845633720955379631305146632105166316364004106707988280921238594013175217609

Recover the original message, M.

Name Solved on
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Nomyo 2015-02-21 01:38
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RageYL_ 2015-04-26 13:10
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ftuknights 2015-11-07 11:46
koaidien 2015-11-07 11:48
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akiym 2016-02-12 16:36
p4p1lio 2016-02-13 22:37
takaki 2016-02-28 05:30
jtwp470 2016-03-19 16:49
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f0rki 2016-07-14 22:51
mosaku 2016-07-27 07:28
cuti 2016-08-22 12:16
yeuchimse 2016-08-30 10:33
okiya 2016-09-07 09:23
x4mp 2016-09-07 13:37
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celeron 2016-09-07 15:45
EvilGeniuses 2016-09-08 14:12
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