Security researcher had to jailbreak their car just to update the clock

A security researcher recently had to resort to reverse engineering their car's infotainment system to update the time, as the original navigation map SD card had been removed. The 2014 Renault Latitude they were driving required this SD card to change the time in the in-car display. The researcher, Rasmus Moorats, had been warned by the previous owner that the SD card was necessary, but he did not believe it.

After purchasing the used car, Moorats found that the time was indeed out of sync by an hour. He decided to adjust the in-car time display, but encountered an issue when a second settings menu, which was supposed to allow the adjustment, produced an error message stating "No maps detected!" Instead of giving up, Moorats decided to reverse engineer the system.

He discovered that the head unit ran a customized Linux-based TomTom operating system on a Samsung SoC. By extracting and analyzing the firmware, building a QEMU environment for the device, reversing the scripting engine, and uncovering vulnerabilities in the system, Moorats gained root-level access to the infotainment system. The date and time settings were found to be stored in /mnt/flash/settings.dat in a custom binary format.

Unlike modern systems, this 2014 Renault Latitude did not have a concept of time zones. Instead, it obtained the time from GPS and stored the local offset as a number of minutes. In Moorats' case, the offset was set to 180 minutes, which he changed to 120 minutes.