[Security] XSS in demos/demo.mysqli.php of getID 3

[seongil-wi]

Describe the bug
Reflected Cross-Site Scripting (XSS) may allow an attacker to execute JavaScript code in the context of the victim’s browser. This may lead to unauthorised actions being performed, unauthorised access to data, stealing of session information, denial of service, etc. An attacker needs to coerce a user into visiting a link with the XSS payload to be properly exploited against a victim.

To Reproduce
Steps to reproduce the behavior:

1. Access to the following link: http://[localhost]/getID3/demos/demo.mysqli.php?encoderoptionsdistribution=1&showtagfiles=%3Cscript%3Ealert(1)%3C/script%3E
2. Boom!

Where the Issue Occurred
The code below displays the user-controlled parameter showtagfiles without sufficient sanitization:

getID3/demos/demo.mysqli.php

Line 1500 in 4e02ed0

echo 'Files with Encoder Options <b>'.$_REQUEST['showtagfiles'].'</b>:<br>';

[StudioMaX]

Well, besides this XSS, there are a lot of other weird problems in the demo files. Therefore, they are disabled by default.

getID3/demos/demo.mysqli.php

Line 15 in 4e02ed0

die('Due to a security issue, this demo has been disabled. It can be enabled by removing line '.__LINE__.' in demos/'.basename(__FILE__));

But in any case, this will be fixed in #342. Thanks!