Html-escape the $currentStyleSheet variable #112
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The
$currentStyleSheetvariable may be populated by aGETrequest parameter (?cssfile=foo) from the client, and is included without being escaped. As such, an XSS vulnerability can be triggered by simply closing the tag and including any arbitrary content or scripts.http://www.csszengarden.com/?cssfile=http:%22%3E%3Cscript%3Ealert(%27hello%27)%3C/script%3E
I understand that content injection and XSS are not particularly important on a site like csszengarden.com, but I believe that this change is nonetheless an improvement.
Thank you for your consideration.