A client device implements a media player and a proxy application. The media player controls playback of media content on the client device. The proxy application is implemented to request a playlist from a media server, where the playlist corresponds to the media content. The proxy application receives the playlist from the media server, and the playlist includes encryption key reference parameters to obtain an encryption key. The proxy application modifies the playlist to include local encryption key access parameters for the media player, and the modified playlist is communicated to the media player. The proxy application can then receive a request for the encryption key from the media player that utilizes the local encryption key access parameters included in the modified playlist, and the proxy application securely communicates the encryption key to the media player.