Update challenge 0

pull/4/head
Maik de Kruif 3 years ago
parent e53dadd1f7
commit 2e6a2f6e82
No known key found for this signature in database
GPG Key ID: 46C1200ACD3A432F
  1. 11
      content/posts/adventofctf/challenge_0.md

@ -25,20 +25,23 @@ Do you remember the flag in the teaser website?
## Solution
Use the Wayback Machine to get the teaser page.
<https://web.archive.org/web/20201112020839/https://adventofctf.com/>
Sadly, the teaser website isn't online anymore. If only someone kept an archive of the internet. This is where the Wayback Machine on [archive.org](https://archive.org/) comes in handy.
When taking a look at the source we find the following comment:
So, let's use the Wayback Machine to get the teaser page. <https://web.archive.org/web/20201112020839/https://adventofctf.com/>
When we take a look at the source html of the page we find the following comment:
```html
<!-- Ceasar worked on this you know. Tk9WSXtIRVlfMVNfVGgxU19AX0ZsYTk/fQ== -->
```
If we then use `base64` to decode this string we get `NOVI{HEY_1S_Th1S_@_Fla9?}`.
It looks like some encoded string. If you've been doing CTFs for a while you'll probably recognize it's encoded in `base64`. We can use the program `base64` to decode this string.
```bash
> echo "Tk9WSXtIRVlfMVNfVGgxU19AX0ZsYTk/fQ==" | base64 -d
NOVI{HEY_1S_Th1S_@_Fla9?}
```
We found the flag! It's `NOVI{HEY_1S_Th1S_@_Fla9?}`.
This flag can then be submitted for the [challenge](https://ctfd.adventofctf.com/challenges#0-1).

Loading…
Cancel
Save