Problem: I found this cipher in an old book. Can you figure out what it says? Connect with nc 2019shell1.picoctf.com 32203.
Solution: Connect nc 2019shell1.picoctf.com 32203
Encrypted message:
Ne iy nytkwpsznyg nth it mtsztcy vjzprj zfzjy rkhpibj nrkitt ltc tnnygy ysee itd tte cxjltk
Ifrosr tnj noawde uk siyyzre, yse Bnretèwp Cousex mls hjpn xjtnbjytki xatd eisjd
Iz bls lfwskqj azycihzeej yz Brftsk ip Volpnèxj ls oy hay tcimnyarqj dkxnrogpd os 1553 my Mnzvgs Mazytszf Merqlsu ny hox moup Wa inqrg ipl. Ynr. Gotgat Gltzndtg Gplrfdo
Ltc tnj tmvqpmkseaznzn uk ehox nivmpr g ylbrj ts ltcmki my yqtdosr tnj wocjc hgqq ol fy oxitngwj arusahje fuw ln guaaxjytrd catizm tzxbkw zf vqlckx hizm ceyupcz yz tnj fpvjc hgqqpohzCZK{m311a50_0x_a1rn3x3_h1ah3x54ioc1h9}
Yse lncsz bplr-izcarpnzjo dkxnroueius zf g uzlefwpnfmeznn cousex mzwkapr, cfd mgip axtfnj 1467 gj Lkty Bgyeiyyl Argprzn.
Ehk Atgksèce Inahkw ts zmprkkzrk xzmkytmkx narqpd zmp Argprzn Oiyh zr Gqmexyt Cousex.
Ny 1508, Jumlntjd Txnehkrtuy nyvkseej yse yt-narqpd zfmurf ceiyl (a sferoc zf ymtfzjo arusahjes) zmlt ctflj qltkw me g hciznnar hzmvtyety zf zmp Volpnèxj Nivmpr.
Hjwlgxz’s yjnoti moupwez fapkfcej ny 1555 ay f notytnafeius zf zmp fowdt. Zmp lubpr nfwvkx zf zmp arusahjes gwp nub dhokeej wpgaqlrrd, muz yse gqahggpty fyd zmp itipx rjetkwd axj xidjo be rpatx zf g ryestyii ppy vmcayj, hhohs cgs me jnqfkwpnz bttn jlcn hzrxjdpusoety.
The name is a hint, researching it you see that la cifra de give you The cipher now known as the Vigenère cipher, however, is that originally described by Giovan Battista Bellaso in his 1553 book La cifra del Sig. Giovan Battista Bellaso. from wikipedia. The cipher is a Vigenère cipher and you can brute force the key or use the key: flag.
Flag: picoCTF{b311a50_0r_v1gn3r3_c1ph3r54ddc1b9}