Zipping through that electronic toll fast-lane on the highway may save you time, but it also may cost you your privacy.
A Black Hat researcher recently reverse-engineered the popular RFID-based FasTrak toll tag that some drivers in the San Francisco Bay Area affix to their windshields for pre-paying highway tolls, and discovered some gaping security holes that leave these transponders vulnerable to sniffing, cloning, and surreptitious tracking of a drivers comings and goings. Nate Lawson, principal with Root Labs, will demonstrate at Black Hat USA next month in Las Vegas what he found inside those toll tags (hint: no encryption), and he will release an open-source tool for users to protect their toll tags from abuse.
The FasTrak transponder provides the users unique identification code -- the drivers toll balance and other financial and personal information are stored on back-end servers. Lawson says its been difficult to get any information on how those servers are locked down, so its unclear how customers personal data is protected. He says hasnt looked at any other toll tag systems such as EZPass -- and whether they leave users vulnerable to breaches of privacy depends on how they collect and handle the data.
Lawson, who lives in the Bay Area, says he initially resisted using the e-toll system for privacy concern reasons. The thing that motivated me to take the transponder apart was that they [California transportation officials] added onto the system an information line to get information about Bay Area traffic... it provides really accurate drive times to the airport, etc. They added readers for the transponders all over light poles on the highways, he says. So in real-time, they are tracking all cars going past with FasTrak tags, he says.
Most likely, [the data] appears there for awhile, so the transponder is subject to hacking, and subpoenas in court cases, for instance, he says.
After cracking the hardware and studying the firmware with help from fellow researcher Chris Tarnovsky, Lawson says he was surprised to see no sign of encryption inside, although theres a placeholder for an encryption key. It amazes me there has not already been widespread fraud, cloning, and selling of free transponders that were hacked and reprogrammed, he says. Theres nothing there technically to prevent it.
Lawson is also researching whether malware could be planted on a FasTrak transponder. Because of the proprietary extensions they [the vendors] added to support the parking lot stuff and other future uses in these devices, the devices could possibly be vulnerable to malware-born hacks as well, he says. He hasnt finished his research on that just yet.
FasTrak, meanwhile, offers an anti-static aluminum envelope in which drivers can place their toll tags after they leave the toll booth, but its awkward -- and potentially dangerous -- to tuck it away while driving, Lawson notes. So hes come up with an alternative way to shield the FasTrak transponder from sniffing and giving out too much information: I designed a daughter-board that you add to the pass. You press a button on it so when you near the toll plaza, it activates RFID, and then immediately cuts the power to the whole circuit when its done, he says.
Lawson will offer the open-source technology for free to any highway officials, vendors, or researchers who are interested, and he says hell provide any expertise gratis to transportation agencies that need assistance in securing their e-toll systems.
Meanwhile, Lawson also is gearing up for another hack on the highway prior to his Black Hat talk, which is titled Highway to Hell: Hacking Toll Systems. He'll run a homegrown sniffer along the freeway that logs messages passing between his toll tag and the tracking systems on freeway light polls. Its neat because you can also monitor other peoples transmissions between the light poles and back, he says.
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