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jebidiah-anthony

write-ups and what not

The_Sword (50 pts)

PART 1 : CHALLENGE DESCRIPTION

Decrypt the following cryptogram.
You received a memo containing an unknown character string from your senior colleague.
He said you would obtain something important by decrypting the memo.

MzU3MzM3MzIzNzMyMzc3NTcyMTIyNTc1MjM1MzU3MTUxNzIzMzI1MTcxMTM3MTU3MTc1NTcyMzIyMzUyMzIzNTcyNzU3MzMyMzIxMjM1NzcNCjc3MzIxNzIzMzE1MjU1Mjc3NTUyNTIyNzU1MTc3NTU1NTcxNTc1NTEyMzM3MjM1MjE1MTIyMjM3MjUzNzUxNzc3MjU3MzMxMTE1MjE3MzczDQoxMTczNTU1NTU1NTMzMjU3NzUyMjcyNTczMj

PART 2 : GETTING THE FLAG

Base64 decode the given “memo”

$ c="MzU3MzM3MzIzNzMyMzc3NTcyMTIyNTc1MjM1MzU3MTUxNzIzMzI1MTcxMTM3MTU3MTc1NTcyMzIyMzUyMzIzNTcyNzU3MzMyMzIxMjM1NzcKNzczMjE3MjMzMTUyNTUyNzc1NTI1MjI3NTUxNzc1NTU1NzE1NzU1MTIzMzcyMzUyMTUxMjIyMzcyNTM3NTE3NzcyNTczMzExMTUyMTczNzMKMTE3MzU1NTU1NTUzMzI1Nzc1MjI3MjU3MzI3NTExMTc3MjczNTUxMTUyMzI3MjIzMjEzMTM3NTE3MjI3MjE1MzMyNTMzMTMzMzc1MjU3MjUKMTU1MjIyMzI1NTc1NTUzNTMxNTIzNTE3NzE3NTM3NzEyMzUzNTc1NTc1Mjc1NzcyNTE1NTExMzU1MjE3MTc3Nzc3NTMxMjE3NTEzNzczMzEKMzIxMTMxMjIxMjI1NTczMjIxMTIxNTc1MTgwMDg3MjAxMjUyMTA3MTU4MTc4ODg1NTg3Nzg3MTExNTEyNzMyNTMzMjcxNzE1MzIxNzE3MjUKMTMzMzczMzU1NzM3NzI1NTU1MjMzNzEyMzAxNTcwNzA1MjU1Nzg3NTE4NTgyMjEwMzgzMzgzNTIzNTUxNTc3MTUxMzE1MjUyMjIyMTIzMjUKMjcxMTI1NzcyMTEzMzM1NzI1MzM3NTMyNzg1MzUwMzg1MjI1MTgxMjc4NTgzMjU4NzAzMDM3MTU3MzMzMzI3NzUzMTU1MTEzMzMzNzExNTIKMzMzNzEzMjE1MjczMTE3MTIzNzU3MTIyNTAzMjE4NTA1NTUyMzAyMTc4MTg1MzUyMjA1ODUyMzE1MTI3NTEzMTU1MTI1NzUxNTEzNzM3MzIKMjUyNzMzNTcxNzUzNzcxNzE3NTMyNzI3MzgwODAyMjAzNTUyMjAyMjIwMTAxNTIxMjAwNTc3MTM1NzE3NzUxMTEzNTEzMzUxMzU3NzU3MjIKNzU3NTM1MjE3MTUxMTIyNTI3Mjc1MjM1NzAyMTMxNTg3NzIxMjAxNzU4MjA1MzU1MTgyODMyNTcxNzc3MzUyMzMyNTM3MTE1NzMxMjIyNTIKMzMyMzE1NTI3NTIyMjE3NzEyNTczMzc1NTg3MzEyNTgyMzMyMzAyNTU4MTg3NTU4NTgxODEzNTc1MzIyMzc1MTU1MjMzNTIzNzU3MTc3MTUKNzIzMjc3MzEzNzU1NzIxNTMzNTI3NzMxNzAzMzc3MzAyNzMzMzg1NTcwMzAyMzc4MTg1MjAzNzc1MTIzMzEyMjUzMTUzNTUyNzczMzc1MjUKMTc3MjcyMTM3NTM1NTU1MTMzMTM1NzUyMTgxMjMyMzg4MDg4MTI4ODAzMzMwODg1NTgxMzA3MTcyNzMxNTExMzEzNTUyMzEyNzUyMjUzNTMKMTMzMTUzMTUzMjI3NTE3NzE3MzI1MjMxMzczNzczMzUzMjIzMjE3NzMyMTEzNTM1MjMyMjE3MjMyMTcyMTMyMTU1NTczMzcyMjU1NTcxNzIKNTcyMzU1MzcyNTM3NTI3MjExNzIyNTM1NTIxNTEzNzc1NzUzNTU1MTE3MjcxMTMyMjU1NTUyMjIzNTI1NTI3NzI1Mzc1MzU1NzU3Mzc3MzUKNTE1NTIxMzcyNTEyNzE3MzExNzUyNzM3MjIyMTE3MzcxMzIzMzE3MjM1MjExNzI1MjUxNTIyNzIyMjUxMzM1MTMzMjMzMzExNTIzMzczNTMKMjMxNzc3MjE3MjU1NTc1MTE3MjI3NTM1MzIxMjczMzczMTEyMTI1NTU3NzMyNzU3MzMxMjM3NzUxNzM3NzI1Mzc3MTM3NzIzMzU1MjIyNzcKNTM3NTMzMzc1NzI1NTI3NTMzNzE1MTE3MzI3MjEyNTEyNzEzMzExMzUzMjEyMzIzNzI1NzM1MTMzMjEzNTU1NzE3NTI3MzEzMTU3MTMxMjIKMTMxMTMyMjU1MjIzMjI3MjIzMjEyMjczMjM1MjcxMTMxMzMxMzMzMzIyMzI1NzMzNzczMjM3MTE3NzMyMzI3NTI3Mzc1NTU1MjUzMjcyMjEKMTExMjcxMTUzMTU1MTUxMTEyMTc1NzcxMTIxNzUxNTIyMzIxNzI3NzU3MzUxMjUzMzM3NzIxNTM1MjcyMTMxMTc1Nzc3MjMzMTMzNzMzMTMKMzI3MTI3MzE3MzEyNTczMTI3MzEyNzUzMTcyMTM3MjEzNzIzNzEyNzMyNzcyMzEy"

$ echo $c | base64 -d

  35733732373237757212257523535715172332517113715717557232235232357275733232123577
  77321723315255277552522755177555571575512337235215122237253751777257331115217373
  11735555555332577522725732751117727355115232722321313751722721533253313337525725
  15522232557555353152351771753771235357557527577251551135521717777753121751377331
  32113122122557322112157518008720125210715817888558778711151273253327171532171725
  13337335573772555523371230157070525578751858221038338352355157715131525222212325
  27112577211333572533753278535038522518127858325870303715733332775315511333371152
  33371321527311712375712250321850555230217818535220585231512751315512575151373732
  25273357175377171753272738080220355220222010152120057713571775111351335135775722
  75753521715112252727523570213158772120175820535518283257177735233253711573122252
  33231552752221771257337558731258233230255818755858181357532237515523352375717715
  72327731375572153352773170337730273338557030237818520377512331225315355277337525
  17727213753555513313575218123238808812880333088558130717273151131355231275225353
  13315315322751771732523137377335322321773211353523221723217213215557337225557172
  57235537253752721172253552151377575355511727113225555222352552772537535575737735
  51552137251271731175273722211737132331723521172525152272225133513323331152337353
  23177721725557511722753532127337311212555773275733123775173772537713772335522277
  53753337572552753371511732721251271331135321232372573513321355571752731315713122
  13113225522322722321227323527113133133332232573377323711773232752737555525327221
  11127115315515111217577112175152232172775735125333772153527213117577723313373313
  327127317312573127312753172137213723712732772312

The ciphertext generated has a lot of 1, 2, 3, 5, and 7 scattered all throughout but 0 and 8 are clustered in the middle.

Marking 0 and 8 gives you:

$ echo $c | base64 -d | egrep --color -e "[80]"

FLAG

FLAG : flag{pluck}