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3 Hardware Trojans in Electronic Devices
and other unauthorized actions. It contains an embedded radio transmitter. It can also
interact with other Trojans of the COTTONMOUTH series.
COTTONMOUTH-II Trojan is a USB implant that helps perform remote unauthorized control over a complex target system. It is connected to other modules hidden
in the computer chassis, which helps establish connection via the radio channel as
well.
COTTONMOUTH-III is a hardware USB implant that ensures hidden connection
to the computer even if it is switched off or inaccessible via network connections. It
connects to other Trojans hidden in the computer chassis and allows connecting to
the victim’s equipment via the radio channel.
FIREWALK is a hardware implant designed as an Ethernet or USB connector and
allows the intruder to intercept data and install exploits via radio channel.
3.2.3 Trojans for Interception of Information Input
via the Computer Keyboard
We have already covered these Trojans in previous sections; however, as noted in
the foreword, chapters of this book can be read in random order; here, we present a
very brief overview of this malware.