Drupal core - Cross Site Scripting (UTF8) Vulnerability
28 Apr. 2012
Summary
When outputting plaintext Drupal strips potentially dangerous HTML tags and attributes from HTML, and escapes characters which have a special meaning in HTML.
Credit:
The information has been provided by tefan Esser, Mayflower GmbH and Zend..
Vulnerable Systems:
* Drupal 4.7.x before version 4.7.11.
* Drupal 5.x before version 5.6.
When outputting plaintext Drupal strips potentially dangerous HTML tags and attributes from HTML, and escapes characters which have a special meaning in HTML. This output filtering secures the site against cross site scripting attacks via user input.
Certain byte sequences that are invalid in the UTF8 specification are not handled properly by Internet Explorer 6 and may lead it to see a multibyte start character where none is present. Internet Explorer 6 then consumes a number of subsequent UTF-8 characters. This may lead to unsafe attributes that were outside a tag for the filter to appear inside a tag for Internet Explorer 6. This behaviour can then be used to insert and execute javascript in the context of the website.
Vendor Status:
Drupal issued an update for this vulnerability
