The IEEE 1588 precision time protocol (PTP) is used by many time-sensitive applications and systems, as it achieves sub-microsecond time synchronization between computer clocks. However, a PTP network is vulnerable to cyber-attacks that can reduce the protocol accuracy to unacceptable levels for some or all clocks in a network with potentially devastating consequences. Of particular concern are advanced persistent threats (APT), where an actor infiltrates a network and operates stealthily and over extended periods of time before being discovered. This paper investigates the impact of the most important APT strategies on a PTP network, i.e., the delay attack, packet modification or transparent clock attack, and time reference attack, using a fully programable and customizable man in the middle device, thereby considering the two most popular PTP slave daemons PTPd and PTP4l. In doing so, it determines suitable attack patterns and parameters to compromise the time synchronization covertly.
Cyber Attacks on Precision Time Protocol Networks—A Case Study