Fields is a GLPI plugin that allows users to add custom fields on GLPI items forms. Prior to 1.21.13, an authenticated user can perform a SQL injection when the plugin is active. The vulnerability is fixed in 1.21.13.
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.