c = 7404228387482887479261869746749991746176804495927055118318206683570516448983801743960459361546161134428690426222368709863453442050071171756423599377401597984440754435058668926603178633761668515076496069751847161724033187368679875259918093224187811267691876198273870870578467510184510086298582204521702946045220312770122458237518246424165432296119053607094777200284200814236416350304918483690156578148133652864328594441673632360773823893061942585188618198600179924877899949396771723157015085683434661302154230334257765610040158570863416499816053904560634890245995407176180498179848769133967582005361790108725945277949845769358752674332269800138008126120486961174643630274131401283073800170609863393091462716402062974615038997250596862336175333249971111165958082179351116528188875511999901288868170989351009565637749016012554778609401305705599425503266370571838403199592830285591168821852287944019050110517938219347052153238370382065390639346971764343981632465382255796047103032366703706122266986406432114737513202337430860123189821063638894815952679576109060674029276361130756827095433943772560556432939992933276440340090287373085788774415087792787958810051460428461265815708830858361853853472340042568141996425244740239642623958541083311687869085046368156034023773742764525490982352637357523475031768768619981883253061696021829604666466769997506990572364386730754183019245389791086458671560767393577689687174730155049027616849606316072012661663516661756810877578172095321431600121667891545760511844723167476314345937930753837239733394626157660380103339672690094231220365695508657679602754981411231543816566131037225152153015287164171129157814773590352342570677841639550177097704155982858059402540582839885549452130954935219771327861980762934458786390322073771612324195542640000816993296528925039288704714097937261854536340516727095307316259517387188619927408613685678242056200319636422554100280245820480283675364454021450870487344889261

Find the flag.

Source is as follows

#!/usr/bin/env python3

import random
import time
import string
import signal

# use secure seed
random.seed(int(time.time()))

with open('flag.txt') as f:
	flag = f.read()

# large constant prime
p = 174807157365465092731323561678522236549173502913317875393564963123330281052524687450754910240009920154525635325209526987433833785499384204819179549544106498491589834195860008906875039418684191252537604123129659746721614402346449135195832955793815709136053198207712511838753919608894095907732099313139446299843

c = 26191355940216514058828050272090150139390105143316571288916153959981987155364392954681002096093811060534927092859120901667895980558351695183915403894182364524347204398303912481028969683750214274848084070775246727321046148252133500795342545499148992521849021332747338401076716206206836615083856166994789822570460117243518366900792518256064537225383342326351881682268623120346344160800766471622876341688831087817377673995827709465873793531598458486278334606573583545504597466349568081151696945328172365621531283265041924009357925158333224321566901753418442265655624943219944771093126875477706910554618181364928356402397

c = 49938873005546615435687311504872509785022284769848698526216639826561007249140360312632267256915204926681345807364733487154803200306964789424438457669341375204871001335059277860364152540205309441986059468568646721718475252818788849738581432943901958543446753508706429359356503196241596325655490713282416769960

Time for RSA!

e = 65537

n = 134023913680045880492110426626164090971954352532495944119602241841766743315344885078078359876157853261789964632342961459801834169156073972150056251259429043527344585589350222304649100454018523375146422111308080990153227407607374257909945989989405880451908900962388521742688809203045971595430040363546058882461

one fish twofish red fish blowfish

0xcaae8ee4f458ff776860e57141313e1e145423932e79e799d5133af8610e40d 94299046d28022d0b0efaa7fd3177b87e8e8530667111180e47da98f84846d753 cf9afa7c2635c93cf93ef8035b2217c05e192e3d2547e084c86085c2b83ef2b5

Solution

The...

There was once a guy, who hadn't anything to do. So he made haiku.

CTF question, related to cryptography, he presents to you.

Solve you can or not, you must at least try or else, you disappoint him.

• Flag Format : /FLAG[A-Z]+/

Provided boring...