The Ultimate Member – User Profile, Registration, Login, Member Directory, Content Restriction & Membership Plugin plugin for WordPress is vulnerable to second-order SQL Injection via filenames in all versions up to, and including, 2.9.2 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with access to upload files and manage filenames through a third-party plugin like a File Manager, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database. The risk of this vulnerability is very minimal as it requires a user to be able to manipulate filenames in order to successfully exploit.
The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.