CrateCTF 2025 Writeup: Den buslätta utmaningen

"Buslätt" is a OSINT challenge that is Swedish for "very easy." It gives you with a logo, a compass pointing South-West, and a text box. While the text claims "you will solve it easily". The goal is to use visual analysis of the sign's logo & the compass direction to get the true location in Sweden.

j3rry

Nov 25, 2025 — 1 min read

1. The Starting Point: The Image

The challenge gave us a text box with coordinates already filled in, but the real investigation started with the image.

We were shown a photo of a logo.

Visual Analysis: The first step was identifying the logo on the sign.
The Clue: The logo belongs to Västtrafik, the public transport agency for West Sweden.

This was the critical first step. It immediately narrowed down our search from "the whole world" to a specific region in Sweden.

logo screenshot whose location had to be uncovered

2. The Name

The challenge title was "Buslätt".

In Swedish, busenkelt means "child's play" or "very easy." "Buslätt" is a pun on that.
However, a quick search revealed that Buslätt is also a real place—a district in the city of Uddevalla.

3. The Compass

The final clue was the cartoon compass at the top of the page. The compass was pointing South-West (SW). The puzzle wasn't asking for the location of Buslätt itself. It was using Buslätt as a reference point and telling us to look in the South-West direction.

4. The Solution

By looking for Västtrafik bus stops in the South-West area of Uddevalla (following the compass), we found the Kärra Södra bus stop.

We grabbed the exact coordinates for the sign at that location: 58.3129688, 11.8787946... And the Flag: cratectf{en_slätt_som_heter_bu}

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