BMW's Software Security Patch A Sign Of Things To Come

BMW's "over-the-air" update transmitted to its ConnectedDrive software running on 2.2 million of its vehicles worldwide this past week to fix security flaws offered a rare glimpse of how the generation of smarter and more network-connected vehicles could get patched when bugs are discovered.

The German carmaker updated the software running in models of the BMW, Rolls Royce, and Mini, in response to the German Automobile Association (ADAC)'s discovery that an attacker could hijack or manipulate remote communications to the vehicles' SIM cards. The researchers reportedly were able to unlock the car doors remotely using a spoofed mobile network tower that intercepted mobile traffic to and from the vehicles.

Researchers at ADAC say the weak and unencrypted mobile communications links to the API also could potentially allow attackers to sniff vehicle location, speed, and even email communications over the ConnectedDrive network.

In response to the researchers' findings, The BMW Group said it now uses HTTPS for encrypted mobile communications to ConnectedDrive vehicles, and that no hardware nor any driving-related functions or personal customer data were affected by the security flaws. "The BMW Group has a new configuration to close this gap.  The update is carried out automatically or when the driver manually updates BMW Assist/ConnectedDrive," the company said. "The online services of BMW Group ConnectedDrive communicate with this configuration via the HTTPS protocol … which had previously been used for the service BMW Internet and other functions," and any communications to the car is authenticated to the BMW Group server before data his the mobile network, the statement said.

The over-the-air patching by BMW demonstrated one way carmakers could handle the inevitable discovery of future security bugs in cars, says Joshua Corman, CTO at Sonatype and a founder of the grass roots I Am The Cavalry effort. "They did an update over the air--no one had to go to the dealer, no one needs to come into the shop. That's a prompt and agile response" to a security issue, he says.

While details of the BMW ConnectedDrive flaws were vague, Corman says software updates indeed should be sent via an encrypted pipe, aka the SSL-based HTTPS. "This is a great response," he says of BMW's approach to the fix. The downside, of course, is that some SSL implementations, such as OpenSSL, have sported security flaws of their own, he notes.

Other cars may not be as patchable as BMW's, either. "Very few companies have the ability to remotely update" their automobile software like BMW has, he says. "It could have been something unpatchable … What if it required different hardware or firmware to fix and it was perpetually exposed for the life of the car?"

Corman helped craft the proposed Five Star Automotive Cyber Safety Program that carmakers can use to shore up the cyber security of their networked vehicles. He says it's still a ***

The five components are:  safety by design, where automakers build automation features with security in mind and employ a secure software development program; third-party collaboration, where automakers establish vulnerability disclosure policies; evidence capture, where automakers log forensic information that could be used in any safety or breach investigation; security updates, where they push software updates to customers efficiently; and segmentation and isolation, where critical systems are kept in a safe sector of the car's network.

[Public safety issues bubble to the top in security flaw revelations. Read Internet Of Things Security Reaches Tipping Point.]

Still unclear is whether BMW actually isolates critical driving functions from Internet browsing or the entertainment system. The company had not yet responded to questions about its cars' network architecture as of this posting. The affected versions of BMW's ConnectedDrive software range from March 2010 to December 2014. ConnectedDrive provides Internet access, navigation, and other networked features via a SIM card installed in the vehicle.

"Is there logical and physical segmentation between critical and non-critical systems? If you compromise the infotainment system, you should not be able to disable the brakes," Corman says.

Concerns over security holes in networked vehicles being used by attackers to cause physical or other damage has intensified in the wake of eye-popping research such as that of renowned security experts Charlie Miller and Chris Valasek.

Valasek, who heads up the vehicle security research practice at IOActive, says the good news is that malicious car hacking hasn't occurred just yet, and researchers are racing to get ahead of the bad guys. "No matter which manufacturer it is who gets hacked the first time, it's going to be an issue for the auto industry in general," Valasek says.

IOActive recently expanded its Vehicle Security Practice, offering secure development lifecycle consulting for automakers as well as penetration testing of vehicles. Valasek says the secure development lifecycle is a key first step to locking down cars from bad hackers, and then a full security assessment. "But a lot of them still don't have the budget and have strong time constraints," he says.

Building new cars with cyber security in mind is key, says Dave Miller, CSO at Covisint, a B2B secure cloud firm with several automotive vendors as clients, including GM's OnStar and Hyundai's BlueLink. "We believe it is important to get this right now, at the beginning, instead of having to retrofit millions of cars," he says. "In this vein, we believe that putting the security infrastructure into the cloud, instead of the vehicle, will allow for the modification of defense strategies as the threat landscape changes."