We get through to a "rotten app" with no JS, links, cookies or anything for us to explore!


The challenge description provided a hint; `Nz Gjstu DUG` is `My First CTF` rotated by 1 (caeser cipher). We can try and [ROT1](https://gchq.github.io/CyberChef/#recipe=ROT13(true,true,false,1)&input=ZmxhZy50eHQ) some endpoints, e.g. `/admin`, `/flag` and eventually find the correct one is `/flag.txt`

We try the endpoint `/gmbh.uyu` and receive the flag.

Flag: `flag{b67779a5cfca7f1dd120a075a633afe9}`

Original writeup (https://book.cryptocat.me/ctf-writeups/2025/nahamcon/web/my_first_ctf).