PicoCTF2018 Cryptography hertz 2 Objective: This flag has been encrypted with some kind of cipher, can you decrypt it? Connect with nc 2018shell.picoctf.com 12521. got this as the result of the nc Let's decode this now! Yws deruo caign pib qekvh ifsa yws ljzm tix. R ujn'y cslrsfs ywrh rh heuw jn sjhm vaiclsk rn Vrui. Ry'h jlkihy jh rp R hilfst j vaiclsk jlasjtm! Iojm, prns. Wsas'h yws pljx: vruiUYP{hechyryeyrin_urvwsah_jas_yii_sjhm_xknrcraynf} the hint says "These kinds of problems are solved with a frequency that metric some analysis" Solution: so let's use letter frequency to try and crack it, some super high level analysis I don't see any double letters that would be like OO in English but we can borrow some logic from the enigma crack, just like every message the Germans were sending ended with Heil Hitler, we know the format of the flag the flag always starts with picoCTF so we can be fairly certain that the letters vruiUYP
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