[SOLVED] Fixing XSS ?

[thryb]

Hi guys,

Lets say there is a xss vuln in my script at

http://www.domain.com/file/"><marquee><h1>vulnerable

How can I fix it ? I have no trouble with fixing the one that affect a variable ie file.php?var=xxx

But how do I fix the one right at the end of a file like the one up here? I dont get the /">.

 

Thanks in advance!

 

[Azu]

Simple

 

Wherever you echo/print user submitted data, just be sure to escape it with something like htmlspecialchars

 

So instead of echo $_GET['variable']; do echo htmlspecialchars($_GET['variable']);

 

This also applies to $_POST and $_SERVER and data retrieved from databases (if people can put stuff into the database, such as in a forum system for example).

[thryb]

Yes that I understand, but in that case

http://www.domain.com/file/"><marquee><h1>vulnerable

there is no variable posted? or is it simply $_GET['']?

[Azu]

$_GET['file'] maybe. Not sure. Post the PHP code that is outputting it and I can tell you.

[MadTechie]

i assume you are using .htaccess

something like

Redirect /blar/file/ /?file=

check that and get the variable

[thryb]

Ok I found out ... thanks both of you for your help! Didnt think about the .htaccess, there was one of my $_GET that wasnt htmlspecialchars and I forgot it was directed by my htaccess

 

Thanks again for your help