A computer-implemented method for protecting user identity within online content providing environments uses a security content management system (CMS) including at least one processor and a memory. The method includes identifying a request for an online content item associated with an online device. The online device is associated with actual device data. The method also includes determining a first characteristic value associated with the actual device data of the online device. The method further includes generating, by the processor, substitute device data. The substitute device data represents at least the first characteristic value. The method also includes providing the substitute device data to an online content provider.