Abstract: A method for determining whether web content intended for transmission from a second device to a first device via a routing device comprises malware is proposed. The method, to be carried out by the routing device, includes receiving at least a part of the web content from the second device, providing to an antivirus service a representation of N bits of the received part of the web content, and receiving, from the antivirus service, test information based on the representation of the N bits provided by the router and indicating whether the web content may comprise malware. An appropriate representation of the N bits of web content serves as a “fingerprint,” sufficiently identifying the entire piece of the web content for the purpose of determining whether or not this piece of web content may contain malware.