Security Risks Discovered in Tesla Backup Gateway

Security researchers today shared findings detailing the security and privacy risks of connecting a Tesla Backup Gateway to the Internet -- and how an attacker could potentially take advantage.

This research, published by Rapid7, builds on previous studies exploring security risks in these devices. The Tesla Backup Gateway is a platform designed to manage battery, grid, and solar power with a common software stack. It determines when the battery needs a charge, when to send energy to the grid, and what source, or mix, of energy should be supplied to a house. To do this, Tesla Backup Gateway communicates with Tesla via Wi-Fi, AT&T mobile, and Ethernet.

Home users can connect to the Tesla Backup Gateway using weak credentials, as explained on the Tesla website. The first time someone logs in, they connect to Wi-Fi and enter their email and the last five characters of the Gateway serial number, which acts as a password. Once logged in, an API call can be used to access the full serial number for future access. The gateway also broadcasts a Wi-Fi access point that uses the same password/serial number, researchers report. 

These devices are exposed to the Internet, researchers point out, meaning anyone can access them, attempt to log in, and play with the configuration. The researchers have tracked at least 379 exposed Tesla Backup Gateway installations located around the world since January 2020. Of these, a subset are commercial-grade Tesla Powerpacks, which are very large battery arrays.

"I am fairly alarmed at the number of these devices on the internet," said Derek Abdine, former director of Rapid7 Labs and current CTO at Censys, in a writeup. While the numbers may be low, "given the devices are massive batteries that deal in high voltage and current, malicious manipulation could lead to potential physical harms." 

Rapid7 contacted Tesla's Product Security team, which reported it was working on mitigating accidental exposure in future security features, Abdine said. Predictable installer passwords have been fixed for newly commissioned Backup Gateway V1 devices (some previously commissioned devices still had them), and all online Backup Gateway V1 devices have had installer passwords randomized. All Backup Gateway V2 devices come with nonpredictable random passwords.

Read Rapid7's full blog post for more information.