Kipod After Free CTF 2019 Write-ups

The KipodAfterFree CTF is a global CTF with many types of challenges, hosted by KipodAfterFree. We have challenges for everyone, from amateur players to experienced ones, so go have a crack at them!
Tupper needs help
We were provided with below challenge’s description.

k=1149088036118748153043577013820072408885949020563817247643416097427609454784316480438935765354843225548041192362989341741100573490073448156985503983059433007456621869088528541601531021805434641158022863321604365912330878796519179999743007778309707144803824547692249224938557620335782675957793640790464297377099274055139536447837590517931851109546855273584874094409665031001792923933599279402800139404046854000506331325067964897620998752717795071450855954081334797627968452316244584618935641960635983970619395200199775096694978239798720856064
According to the challenge’s tittle and description, this challenge is related to Tupper’s Self-Referential Formula. In order to decode the flag, we use this online tool.

Based on the output above, the flag for this challenge is KAF{MY_KIPOD_IS_HUGE}
SmellyOnion
We were provided with below challenge’s description and a file.

We checked the detail of the zip and it had interesting value in comment.

This comment also show up during extraction, so we extracted all the nested zip.

We combined all the zip comments and got this hex 4b41467b3231505f5048314c33325f525f41573353304d335f44304e545f5930555f5448314e4b7d. Then we decoded it to text and got the flag for this challenge which is KAF{21P_PH1L32_R_AW3S0M3_D0NT_Y0U_TH1NK}
Dinary
We were provided with below challenge’s description and a file.

We tried several tools with no result. We then tried to run zsteg
on it and got the flag.

Based on the output above, the flag for this challenge is KAF{wh3r3_1s_my_k1p0d?}