Patent attributes
Methods, apparatus and computer software products implement embodiments of the present invention that include protecting a computing system by defining a list of network access messages that are indicative of human use of computing devices, and extracting, from data traffic transmitted over a data network connecting a plurality of the computing devices to multiple Internet sites, respective transmissions from the computing devices to the Internet sites. A given transmission including one of the network access messages in the list is detected in the transmissions from a given computing device, and the given computing device is classified as being operated by a human in response to detecting the given transmission. Upon identifying suspicious content in the transmissions from a subset of the computing devices that includes the given computing device, any suspicious transmissions from the given computing device are ignored in response to the classification.