Challenge - Substitution Cipher

Der folgende Ciphertext wurde mit einem "substitution cipher" verschlüsselt. Der Verschlüsselungscode einer Substitutionsverschlüsselung ist eine zufällige Permutation des Klartextalphabets (in diesem Fall: die 26 Buchstaben des lateinischen Alphabets). Die Verschlüsselung erfolgt, indem jedes Zeichen des Klartextes durch das entsprechende Zeichen aus dem Schlüssel ersetzt wird. Der Klartext ist, abgesehen von der Flag, in englischer Sprache geschrieben.

RL OUGCHWIUJCAG J YBNYHRHBHRWL ORCASU RY J QSHAWX WF SLOUGCHRLI NG KAROA BLRHY WF CDJRLHSVH JUS USCDJOSX KRHA ORCASUHSVH JOOWUXRLI HW J FRVSX YGYHSQ HAS BLRHY QJG NS YRLIDS DSHHSUY HAS QWYH OWQQWL CJRUY WF DSHHSUY HURCDSHY WF DSHHSUY QRVHBUSY WF HAS JNWTS JLX YW FWUHA HAS USOSRTSU XSORCASUY HAS HSVH NG CSUFWUQRLI HAS RLTSUYS YBNYHRHBHRWL YBNYHRHBHRWL ORCASUY OJL NS OWQCJUSX KRHA HUJLYCWYRHRWL ORCASUY RL J HUJLYCWYRHRWL ORCASU HAS BLRHY WF HAS CDJRLHSVH JUS USJUUJLISX RL J XRFFSUSLH JLX BYBJDDG MBRHS OWQCDSV WUXSU NBH HAS BLRHY HASQYSDTSY JUS DSFH BLOAJLISX NG OWLHUJYH RL J YBNYHRHBHRWL ORCASU HAS BLRHY WF HAS CDJRLHSVH JUS USHJRLSX RL HAS YJQS YSMBSLOS RL HAS ORCASUHSVH NBH HAS BLRHY HASQYSDTSY JUS JDHSUSX HASUS JUS J LBQNSU WF XRFFSUSLH HGCSY WF YBNYHRHBHRWL ORCASU RF HAS ORCASU WCSUJHSY WL YRLIDS DSHHSUY RH RY HSUQSX J YRQCDS YBNYHRHBHRWL ORCASU J ORCASU HAJH WCSUJHSY WL DJUISU IUWBCY WF DSHHSUY RY HSUQSX CWDGIUJCARO J QWLWJDCAJNSHRO ORCASU BYSY FRVSX YBNYHRHBHRWL WTSU HAS SLHRUS QSYYJIS KASUSJY J CWDGJDCAJNSHRO ORCASU BYSY J LBQNSU WF YBNYHRHBHRWLY JH XRFFSUSLH CWYRHRWLY RL HAS QSYYJIS KASUS J BLRH FUWQ HAS CDJRLHSVH RY QJCCSX HW WLS WF YSTSUJD CWYYRNRDRHRSY RL HAS ORCASUHSVH JLX TROS TSUYJ CJG YCSORJD JHHSLHRWL HW HAS ESG RH RY LWH JDKJGY CWYYRNDS HW XSURTS J OWQCDSHS QJCCRLI WF OAJUJOHSUY RF HAS CDJRLHSVH XWSY LWH OWLHJRL JDD OAJUJOHSUY WF HAS JDCAJNSH HAS JNWTS MBWHS FUWQ KRERCSXRJ XWSY LWH OWLHJRL HAS DSHHSUY PEZ FWU SVJQCDS JXXRHRWLJDDG ASUS RY GWBU FDJI HW YBNQRH FAKOXCCLQRYVQSXNEUEOPWQJXDCIQESX