October CMS through 1.0.431 allows XSS by entering HTML on the Add Posts page.

October CMS through 1.0.428 does not prevent use of .htaccess in themes, which allows remote authenticated users to execute arbitrary PHP code by downloading a theme ZIP archive from /backend/cms/themes, and then uploading and importing a modified archive with two new files: a .php file and a .htaccess file. NOTE: the vendor says "I don't think [an attacker able to login to the system under an account that has access to manage/upload themes] is a threat model that we need to be considering.

October CMS build 412 is vulnerable to file path modification in asset move functionality resulting in creating creating malicious files on the server.

October CMS build 412 is vulnerable to PHP code execution in the asset manager functionality resulting in site compromise and possibly other applications on the server.

October CMS build 412 is vulnerable to PHP object injection in asset move functionality resulting in ability to delete files limited by file permissions on the server.

October CMS build 412 is vulnerable to Apache configuration modification via file upload functionality resulting in site compromise and possibly other applications on the server.

October CMS build 412 is vulnerable to stored WCI (a.k.a XSS) in brand logo image name resulting in JavaScript code execution in the victim's browser.