Prof. M. Eista Hax
300 (+90) Points by lama (Web)
Professor M. Eista Hax uses a digital tool to manage all his students. He is very happy with the system, but it does have one drawback: it does not support multiple users. This is a problem, because M. Eista Hax has employees who need access as well. To solve this he writes a super modern, highly encrypted web application to share the password with authorized users. Problem solved. 

So... Get that key! 
Link (https://school.fluxfingers.net:1501/)


Announcements for Prof. M. Eista Hax

(Published on 2015-10-21 12:54:03)
The first step to solve this challenge is to get the source code of the site. You will need it to solve the second part, i.e. the bug is in the script.
(Published on 2015-10-20 19:44:38)
For some users the time of the server and their own time did not match, so for the server the key was generated in the future. By default this means that GPG does not encrypt a message and stops instead. The site now uses --ignore-valid-from, so this should hopefully not happen anymore. If the output is still empty after uploading a valid public key please let us know in the IRC channel. 

The server time is also synchronized again.
(Published on 2015-10-20 17:02:27)
You do not have to break crypto to solve this task. It also does not include any low-level exploiting.