Vulnerable Systems:
* Drupal 4.7.x before version 4.7.8.
* Drupal 5.x before version 5.3.
The allowed extension list of the core Upload module contains the extension HTML by default. Such files can be used to execute arbitrary script code in the context of the affected site when a user views the file.
Revoking upload permissions or removing the .html extension from the allowed extension list will stop uploads of malicious files. but will do nothing to protect your site against files that are already present. Carefully inspect the file system path for any HTML files. We recommend you remove any HTML file you did not update yourself. You should look for , CSS includes, Javascript includes, and onerror="" attributes if you need to review files individually.
Vendor Status:
Drupal issued an update for this vulnerability
