Drupal's JSON:API and REST/File modules allow file uploads through their HTTP APIs. The modules do not correctly run all file validation, which causes an access bypass vulnerability. An attacker might be able to upload files that bypass the file validation process implemented by modules on the site.
The Form API in Drupal 6.x before 6.37 and 7.x before 7.39 does not properly validate the form token, which allows remote attackers to conduct CSRF attacks that upload files in a different user's account via vectors related to "file upload value callbacks."
modules/openid/xrds.inc in Drupal 6.x before 6.33 and 7.x before 7.31 allows remote attackers to have unspecified impact via a crafted DOCTYPE declaration in an XRDS document.
In Drupal versions 8.4.x versions before 8.4.5 when using node access controls with a multilingual site, Drupal marks the untranslated version of a node as the default fallback for access queries. This fallback is used for languages that do not yet have a translated version of the created node. This can result in an access bypass vulnerability. This issue is mitigated by the fact that it only applies to sites that a) use the Content Translation module; and b) use a node access module such as Domain Access which implement hook_node_access_records().