GPS vulnerabilities could open grid to hacks — DHS report
A newly disclosed government report warns that the power grid may become more vulnerable to hacking attacks on the Global Positioning System as grid operators expand the use of advanced monitors that depend on GPS signals.
The report by the Department of Homeland Security noted that timing signals transmitted from GPS system satellites are crucial inputs to synchrophasor systems that track operating conditions on the grid in millisecond intervals. Nearly 2,000 of the systems were installed on the North American grid as of the end of last year. Most of the rollout was funded by the 2009 American Recovery and Reinvestment Act.
The GPS signals used by the grid, the aircraft industry, financial markets and other civilian sectors, are vulnerable to attack, according to the DHS report, written in November 2012. The report was released under the Freedom of Information Act and published by the noncommercial Governmentattic.org website.
Successful attacks could including jamming to interrupt transmissions between satellites and ground receivers and “spoofing,” which delivers bogus data to ground receivers.
Attacks could disable or render useless the advanced grid-monitoring systems called phasor measurement units (PMUs). The time signals from atomic clocks in GPS satellites allow grid operators to assemble operating data from many PMUs to get a wide-angle view of grid conditions. Interfering with sychrophasor data could deny grid operators the most accurate data on voltages, frequencies and generator alignments, all of which must be closely controlled at all times.
“The Energy Sector depends on GPS for providing electrical power system reliability and grid efficiency, synchronizing services among power networks, and finding malfunctions within transmission networks,” according to the report, “National Risk Assessment — Risks to U.S. Critical Infrastructure from Global Positioning System Disturbances.”
“The electricity subsector currently has sufficient redundancies in place to withstand most GPS disruptions, although spoofing attacks against multiple targets could cause significant service outages. However, as the electricity subsector becomes increasingly reliant on phasor measurement units (PMUs) as part of the smart grid evolution, vulnerability to GPS disruption could increase,” the DHS report said..
