DC25 CPV Workshop slide deck
Try it yourself! (Hint: Use this tool)

Defcon 20 Uber Badge cipher
QMMDYPSQ
SAMSPMQJ
LTYVRXHB
KYRDSZJY
HBGSNQHQ
BWLVJVPM
FUISDCGW
XATLEOBU
LNIHPCSP
TFPWIISX
WTAMTXSV
HTFLHWVV
NWPPWYIP
LDQFIJWT
YCILZGTX
MUDAFPCU
KPNTOXJS
NVSTMLUX

Defcon 23 Uber Badge cipher
BVFBHGHXAWJEKEDMDZAP
RMWGNMTVIRPWIKHGIPUU

Challenge Problem
BJOAM WNJVD TGHQH DRRAN XDLXM DUTSK SNCCO
WAEWM FQEGK QZVTR FIEXW WQGYU TSCGL NHSVE
XSRRL ZPJSR IBLPL JIISP AERJJ PAFYG MQWRW
XWXIE VBJIW YBXFI EGNPR MSUTA WMLZF KEERU
AHGSI YWZGR BHMCP UENWJ TWUOG HAWDR KIOJR
PWLRL CGHMP ZIFMF PPKOS VLLQV GBMOZ VTFKC
VHZG