The Amazon AWS module before 7.x-1.3 for Drupal uses the base URL and AWS access key to generate the access token, which makes it easier for remote attackers to guess the token value and create backups via a crafted URL.
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Amazon AWS. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 9.8.