CODEGATE2010 CTF Level 11
Here's my last writeup, as in the time available I was not able to solve more.
maybe I'll publish writeups of the ones solving right now but I'm not sure yet.
Level 11's description was:
When looking at the website I tried to upload some sample files, tried to change the path were files are saved and so on but nothing of that worked.
After that I decided to focus on the upload filter and collected some information about the host/webserver.
As soon as I saw the HTTP response header was : Server: Microsoft-IIS/6.0
I was pretty sure that the vulnerability which will help me is this one:
Soroush Dalili has discovered a vulnerability in Microsoft Internet Information Services (IIS), which can be exploited by malicious people to potentially bypass certain security restrictions and compromise a vulnerable system. The vulnerability is caused due to the web server incorrectly executing e.g. ASP code included in a file having multiple extensions separated by ";", only one internal extension being equal to ".asp" (e.g. "file.asp;.jpg"). This can be exploited to potentially upload and execute arbitrary ASP code via a third-party application using file extensions to restrict uploaded file types.
I was lucky enough that it really worked :)
The problem I had now was:
Executing commands on the server was not possible, so let's try to read the registry directly with php and print the result.
I used this simple example I found via google:
After uploading the new file I saw following string printed in my browser:
Level 11 solved as well :)
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