[SecurityValley CTF] capture message

암호 문제이다. 메시지의 내용을 알아내는 것이 문제!

깃업에 들어가서 텍스트를 복사한다.


<문제 텍스트>
Riihuhg vdb ylvlwhg hoghuob dqg. Zdlwhg shulrg duh sodbhg idplob pdq iruphg. Kh bh ergb ru pdgh rq sdlq sduw phhw. Brx rqh ghodb qru ehjlq rxu iroob dergh. Eb glvsrvhg uhsoblqj pu ph xqsdfnhg qr. Dv prrqoljkw ri pb uhvroylqj xqzloolqj.

Dsduwphqwv vlpsolflwb ru xqghuvwrrg gr lw zh. Vrqj vxfk hbhv kdg dqg rii. Uhpryhg zlqglqj dvn hasodlq gholjkw rxw ihz ehkdyhg odvwlqj. Ohwwhuv rog kdvwlob kdp vhqglqj qrw vha fkdpehu ehfdxvh suhvhqw. Rk lv lqghhg wzhqwb hqwluh iljxuh. Rffdvlrqdo glplqxwlrq dqqrxqflqj qhz qrz olwhudwxuh whuplqdwhg. Uhdoob uhjdug hafxvh rii whq sxoohg. Odgb dp urrp khdg vr odgb irxu ru hbhv dq. Kh gr ri frqvxowhg vrphwlphv frqfoxghg pu. Dq krxvhkrog ehkdylrxu li suhwhqghg. Brx fdq xvh wklvmxolxv dv iodj exw grqw irujhw wr irupdw. Qrz lqgxojhqfh glvvlplodu iru klv wkrurxjkob kdv whuplqdwhg. Djuhhphqw riihqglqj frppdqghg pb dq. Fkdqjh zkroob vdb zkb hoghvw shulrg. Duh surmhfwlrq sxw fhoheudwhg sduwlfxodu xquhvhuyhg mrb xqvdwldeoh lwv. Lq wkhq gduh jrrg dp urvh euhg ru. Rq dp lq qhduhu vtxduh zdqwhg.



보통 암호문제 1단계들은 시중에 나와있는 암호인 겅우가 많아서! criptii 사이트에 들어가 여러 암호를 이용해 해독해주었다.


그 결과

시저암호로 해독됐다! 해독된 평문을 읽어보니 앞 뒤가 맞지 않는 다양한 단어를 조합한 문장이었다.

어쩐지... 암호문제를 처음 보면 문장 첫 단어로 자주 쓰는 단어인 the 같은 걸로 시프트암호인지 확인을 하는데 유독 보이지 않더라니.


<해독 평문>
Offered say visited elderly and. Waited period are played family man formed. He ye body or made on pain part meet. You one delay nor begin our folly abode. By disposed replying mr me unpacked no. As moonlight of my resolving unwilling. Apartments simplicity or understood do it we. Song such eyes had and off. Removed winding ask explain delight out few behaved lasting. Letters old hastily ham sending not sex chamber because present. Oh is indeed twenty entire figure. Occasional diminution announcing new now literature terminated. Really regard excuse off ten pulled. Lady am room head so lady four or eyes an. He do of consulted sometimes concluded mr. An household behaviour if pretended. You can use thisjulius as flag but dont forget to format. Now indulgence dissimilar for his thoroughly has terminated. Agreement offending commanded my an. Change wholly say why eldest period. Are projection put celebrated particular unreserved joy unsatiable its. In then dare good am rose bred or. On am in nearer square wanted.


해독된 평문 중 flag라는 단어를 포함한 문장이다! thisjulius가 플래그라고 생각해 플래그 형식에 맞춰 정답을 입력했다.

SecVal{thisjulius}

정답!