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Alice has two friends: Daniel and Daniel. So, to distinguish them, she calls them D1 and D2.

They both have a different RSA exponent: D1 uses e1=5, and D2 uses e2=7, but, unfortunately, have an identical RSA modulus N:

N=100000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000267000000000000000000000000000000000000000000000062211

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

  • C1 = M^e1 mod N to D1,
  • C2 = M^e2 mod N to D2.

She sends:

C1=48422511473521990375450896712899456383681349730838556629917526122372944503717161611542955850315226184440439228437399447916137445172653220231750594300230934894206506460735998916154380260461651842230328

C2=36935080566066809987512294593587165922689453239298365979934220773749515302662979395941264100472936036371948284005185898445333990657405117584787357541912376801751380784444605679758201704557692583862275

Recover the original message M.

Name Solved on
tunelko 2014-12-17 00:32
leonidkokhnovych 2014-12-19 13:48
denstadnyk 2014-12-19 13:51
deadmanshat 2014-12-19 18:41
bait 2014-12-19 18:41
Rost 2014-12-20 17:44
STV_93 2014-12-20 17:44
Avenger93 2014-12-20 17:45
GreyFox 2014-12-20 18:03
Kireienko 2014-12-20 18:42
olol 2014-12-20 23:56
unsigned6 2014-12-20 23:59
FB-41_NTUU_KPI_PTI_UA 2014-12-21 11:50
madeofsolar 2014-12-24 14:14
Neodyblue 2014-12-28 18:47
hatrix 2014-12-29 16:34
snaipe 2014-12-30 12:22
Bmoc 2014-12-31 15:16
Greed_ 2015-01-06 22:45
gourvy 2015-01-31 12:42
Nomyo 2015-02-20 05:29
plop 2015-02-24 13:28
RageYL_ 2015-04-21 16:51
Tilon 2015-06-19 19:45
basis 2015-06-26 16:41
saiki 2015-06-29 13:41
eshiho 2015-08-08 17:17
seccamp_group_a 2015-08-08 17:36
193s 2015-08-26 18:59
nanuyokakinu 2015-08-28 14:31
Bono 2015-09-01 15:09
Charo 2015-09-10 10:11
Fulcrum 2015-10-04 13:38
harvey 2015-11-06 13:11
hama 2015-12-09 03:27
kev 2015-12-09 09:39
katoumegumi 2015-12-12 13:57
owlinux 2015-12-20 01:45
nomeaning 2015-12-22 18:00
pall0c 2016-02-07 09:35
Shellisme 2016-02-12 01:59
akiym 2016-02-12 16:26
p4p1lio 2016-02-13 22:36
takaki 2016-02-28 05:09
d2verb 2016-03-09 16:48
jtwp470 2016-03-24 08:44
wxbn 2016-06-24 21:02
f0rki 2016-07-14 17:41
x4mp 2016-08-18 11:50
cuti 2016-08-29 16:50
yeuchimse 2016-08-30 10:29
matbrik 2016-09-07 13:07
celeron 2016-09-07 15:43
EvilGeniuses 2016-09-08 14:32
koaidien 2016-09-08 16:21
okiya 2016-09-08 18:56
Doflamingo 2016-09-09 15:20
Creed 2016-09-11 13:29
cryptosessiontemp123 2016-09-15 19:36
diegosunshine 2016-09-15 20:59
gast04 2016-09-17 10:12
marteun 2016-10-07 09:58
EKorobov 2016-10-11 00:33
HD67 2016-11-04 07:03
Kyuri 2016-11-08 09:40
Ne0Lux-C1Ph3r 2016-11-30 10:05
LazySloth 2016-12-09 18:19
WoLf_56 2016-12-13 21:42
Achi 2016-12-14 13:17
gen 2016-12-26 05:51
daasdingo 2017-01-13 18:44
wolvg 2017-01-13 18:44
__kaydoubleu__ 2017-01-13 19:26
Kh4L 2017-01-17 01:14
YouOnlyPragmaOnce 2017-01-23 20:33
Issun 2017-01-24 00:14
BZHugs 2017-02-11 13:55
chrisrdlg 2017-02-28 16:38
downey_j 2017-03-02 11:01
mosaku 2017-03-12 12:22
mickdermack 2017-03-15 13:55
orisano 2017-03-15 14:29
giech 2017-03-23 01:59
birabira 2017-03-24 03:53
regulus 2017-04-05 10:24
tydef123 2017-04-26 19:49
amok 2017-05-15 20:52
ommadawn 2017-05-25 12:27
FumesOver 2017-07-15 18:11
lowener 2017-08-05 05:03
Antoxyde 2017-08-13 21:18
duy 2017-08-21 09:22
multun 2017-08-21 14:10
totem 2017-09-08 01:30
ngonghia.ctf 2017-10-08 13:01
congacon 2017-10-10 03:13
sisterrain 2017-10-10 09:24
XiaoXiaoHu 2017-10-10 16:21
black_goat 2017-10-12 03:05
vneu 2017-10-26 18:01
liworada@p33.org 2017-11-06 23:22
null123 2017-11-08 05:11
nguydinhthanh 2017-11-12 07:30
csej 2017-11-24 14:15
tictactoe 2017-12-08 07:56
badc0ded 2017-12-18 13:17
Sideway 2018-01-12 18:57
squalltan2000 2018-01-13 03:38

Current top 10

Rank Name Points
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2nd awe 6736
3rd Creed 6140
4th RageYL_ 5850
5th f0rki 5480
6th wolvg 4976
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8th nanuyokakinu 4016
9th takaki 3756
10th Bono 3746
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