Recently, searching the net I found a vulnerability on the site sin0nime.com.
It is a Cross Site Scripting (XSS) vulnerability.
Visiting the original site is no danger, the site is safe and does not contain any malicious code. The problem occurs when a user sends a link, which he has previously modified, to another user. What can happen to you? A window may open with a message, you may be redirected to another site, etc.
Obviously I was curious to see what the vulnerability was, and I did the research on openbugbounty.org. He was the same guy who reported another vulnerability a few months ago.
Continuing the research, I also found out the code that was used to discover the vulnerability.
Here is the code used:
/dex/index.php?m=0">ScanT3r<svg/onload=confirm(/ScanT3r/)>web"&cheie=Stringent
Another example of malicious script:
cheie="></title></script><svg/onload=alert(1)>&m="></title></script><svg/onload=alert(1)>
In fact, here is a screenshot with some tentative:
The solution is simple, the input data must be verified and validated and modified if necessary. Another solution is to use a class designed specifically for this, e.g. HTML Purifier.
Example,
m = 0 "> ScanT3r <svg / onload = confirm (/ ScanT3r /)> web"
will become
m = 0