r/ciphers

RGBsec does not endorse (or really even know at this point) what the content is on that sub reddit. (It’s just the title of the challenge)

Files

• 11.txt

Solution

The given text file contains some substituted text. Among the text the substring xqoJNM{blpn_4pg_nf3_wan3xa3n_n0_t3jxsdn_wn} looks like the flag. On decoding, xqoJNM should definitely be rgbCTF (flag format), using this a mapping among letters can be created such as x -> r, q -> g and so on. But this wasn’t sufficient, so I used another substring which resembled a URL fnndp://w.xitt.wn/1d7y8g0272851.bdq assumed fnndp to be https and bdq to be jpg, with this I had ample amount of mapping to decode the flag by generating words based on pattern using https://word.tips/.

Flag

rgbCTF{just_4sk_th3_int3rn3t_t0_d3crypt_it}