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rsa3.txt	feat: grouped the challs	2024-01-09 16:59:32 +07:00

README.md

RSA3

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About the Challenge

We were given a file that contain 2 modulus, public exponent, and 2 ciphertexts

n1 = 26936730986023789726214222876998431579035871765812234385674097050592112272540329063679602773116293498245937781951160051718036177035087801218359133356523071700951108999020905116034905584806261203518345118128714311038590925635180342040347317022008233631809623824589107373210514331169745651687793393307158179191306187356408951648269495142386375021669218752561961647301029204701333026044435685936341126368602940601101599988477874713569476970068734357580527463645209944448988010693985476127837819331701523891965427561798033127731232916390511986369304971158889254173850566560028528340860519614489276904182246324437302697433

e1 = 65537

c1 = 25934221721388531303090294836956821212346696995428676440185777623629033147440636130540319272854260855117016879903925227836710795492438220977864741830686432435183222727791461378988782191893620213711460265022633971293289987925875691438890670054518553696690583070284033592035281829227897938832962322172505881421894428362134145126751766514249801481330619906708370005958557827981820321861133293595400304305721764486699677941331024345924352161482159664366018182446127343098427579677894070842066840562853624060861183697917208697602208453017595582242281467105778066369782229287834403074433848470534633158573935584429007575715


n2 = 20923351960149847207730448386993771286287991808293298691185156471519720793292179321382926775933281826329369963004005667653815105072159583791658532166606431385861980687037872135521884790087813454844716254644626942821490878728677736261700329782075809716063515721266692286574071240561529911159730824490258866613280873755548760004314650585913096197607936750263556276920577987540676841745347308103070523989154846358123142014592046611945781700690640990848003152423310523158983857208127158850925297742214928064334410930947749935069628731105093722212442331657106356911123912454871778728334875010902513275561639806401894881233

e2 = 65537

c2 = 5993773597007465934515223705550947500391213737662065644971977783446564890828050443747162704068048188331597029929182281837445674583301936037963788912954366180921337518251139032904603786774772009913305609053718347365864177247549192649908207240197602397010006677485658506955283638199651692990436006544549785434255965098715363287267470252318128158357490592521797199393154974403123099999366644663048724011101287811844340320520544010179529188112211115440469084617438296961494801221969674213288489675624156545941630517075958425681203711654677553772595530799489102830165490202523397154229276688719481530893488434863906070343

How to Solve?

In this case im using X-RSA to recover the plaintext, and because then choose the 14th option

byuctf{coprime_means_factoring_N_becomes_much_easier}