organisation's internet (for the need of surveillance or updates) or the public internet, and are no longer effectively and permanently air gapped, including thermostats with internet connections and automobiles with Bluetooth, Wi-Fi and cellular phone connectivity. Limitations Limitations imposed on devices used in these environments may include a ban on wireless connections to or from the secure network, or similar restrictions on EM leakage from the secure network through the use of TEMPEST or a Faraday cage. Despite a lack of direct connection to other systems, air-gapped networks have been shown to be vulnerable to attack in various circumstances. Scientists in 2013 demonstrated the viability of air gap malware designed to defeat air gap isolation using acoustic signaling. Shortly after that, network security researcher Dragos Ruiu's BadBIOS received press attention. In 2014, researchers introduced AirHopper, a bifurcated attack pattern showing the feasibility of data exfiltration from an isolated computer to a nearby mobile phone, using FM frequency signals. In 2015, BitWhisper, a covert signaling channel between air-gapped computers using thermal manipulations was introduced. BitWhisper supports bidirectional communication and requires no additional dedicated peripheral hardware. Later in 2015, researchers introduced GSMem, a method for exfiltrating data from air-gapped computers over cellular frequencies. The transmission - generated by a standard internal bus - renders the computer into a small cellular transmitter antenna. ProjectSauron malware discovered in 2016 demonstrates how an infected USB device can be used to remotely leak data off of an air-gapped computer. The malware remained undetected for 5 years and relied on hidden partitions on a USB drive not visible to Windows as a transport channel between the air-gapped computer and a computer connected to the internet, presumably as a way to share files between the two systems. NFCdrip was the name given to the discovery of stealthy data exfiltration through NFC (Near-field communication) radio abuse and signal detection in 2018. Although NFC enables devices to establish effective communication by bringing them within a few centimeters of each other, researchers showed that it can be abused to transmit information at a much longer range than expected - up to 100 meters. In general, malware can exploit various hardware combinations to leak sensitive information from air-gapped systems using "air-gap covert channels". These hardware combinations use a number of different media to bridge the air-gap, including: acoustic, light, seismic, magnetic, thermal, and radio-frequency. Software updates From a security perspective, the main