# Defcamp 2018 Quals: Broken TV
![date](https://img.shields.io/badge/date-22.09.2018-brightgreen.svg)  ![solved in time of CTF](https://img.shields.io/badge/solved-in%20time%20of%20CTF-brightgreen.svg)  ![misc category](https://img.shields.io/badge/category-misc-lightgrey.svg)![score](https://img.shields.io/badge/score-330-blue.svg)![solves](https://img.shields.io/badge/solves-17-brightgreen.svg)
## DescriptionAn experienced hacker gained unauthorised access into a facility with limited options to exfiltrate data but he managed to launch a backdoor to solve this issue. However, he got arrested before intercepting the confidential data. Can you recover the information and maybe do some profits on his behalf? Flag format: `DCTF\{[A-Za-z0-9\-]+\}`  **For this challenge you are allowed to scan using nmap, but it won't help you too much :)**  Target: 104.248.38.191
## SummaryAnalyse `ping` time response
## Flag```DCTF{EXF1LTRAT3-L1K3-4-PR0-1S-4W3S0M3}```
## Detailed solutionAfter pinging the server with `ping 104.248.38.191`, we observe that the response time is in interesting ranges: *under 200*(must be ignored), *greater than 200 and smaller than 1000*(binary 0), *above 1000*(binary 1).  We create some files with pings result and a **Python** [script](solve.py) that analyses and converts them in *binary digits*. Then, we use an [online tool](www.rapidtables.com/convert/number/binary-to-ascii.html), with additional padding and extract some parts of the flag, that helps us to reconstruct the valid flag.