Rating:
## [See original writeup on site](https://barelycompetent.dev/post/ctfs/2021-04-11-ritsecctf/#robots)
### Robots
> Robots are taking over. Find out more.
>
> 34.69.61.54:5247
>
> Author: f1rehaz4rd
Given the site URL, and the name of the challenge, we probably are interested in the `/robots.txt` file:
Scrolling through here, we find the following entry:
```
...
Disallow: /patents/download/
Disallow: /patents/pdf/
Disallow: /patents/related/
Disallow: /scholar
Disallow: /citations?
Allow: /flag/UlN7UjBib3RzX2FyM19iNGR9
Allow: /citations?user=
Disallow: /citations?*cstart=
Allow: /citations?view_op=new_profile
Allow: /citations?view_op=top_venues
Allow: /scholar_share
...
```
Notice, that **Allow: /flag/UlN7UjBib3RzX2FyM19iNGR9** entry. Navigating to that in the browser yields a 404. After a bit of guessing, I realized I should try to base64 decode the value, as it looked like an appropriate blob.
So,
```bash
echo UlN7UjBib3RzX2FyM19iNGR9 |base64 -d
RS{R0bots_ar3_b4d}
```
