A server can receive data about attributes of user devices that includes sensors for capturing information about environments in which the user devices are located. The server can determine various risk profiles using the attributes. The risk profiles can indicate likelihoods of content on the user devices being viewed by persons other than users of the user device. The server can also transmit data indicating a risk profile of the various risk profiles to a user device. The user device can use the risk profile received from the server to identify confidential content displayed on the user device and protect the confidential content.