The importdata function of the Simple 301 Redirects by BetterLinks WordPress plugin before 2.0.4 had no capability or nonce checks making it possible for unauthenticated users to import a set of site redirects.
The exportdata function of the Simple 301 Redirects by BetterLinks WordPress plugin before 2.0.4 had no capability or nonce checks making it possible for unauthenticated users to export a site's redirects.