# Security Flaw in 2 Million Vehicles: KARR Alarm System Can Be Hacked Bluetooth vulnerability allows takeover of vehicle controls. - **Source:** [Schneier on Security](https://brifing.si/source/7aee9996-c7c0-47f7-89ec-66a1ed95f8cc) - **Published:** 2026-08-05 - **Topic:** [Software & Engineering](https://brifing.si/c/engineering) - **Original article:** - **On Brifing:** https://brifing.si/s/6d35f479-2851-4d75-911a-129f30a61471 ## Widespread Security Vulnerability A security research team at UC San Diego discovered a critical flaw in the KARR Security System, installed in over 2 million vehicles across the US. Any hacker within Bluetooth range can unlock cars, disable alarms, or even shut off ignitions, leaving drivers stranded. This vulnerability threatens the safety of millions of drivers and requires immediate attention. ## System Vulnerability Details Researchers found that the KARR system lacks sufficient Bluetooth encryption, allowing anyone to send simple radio commands and control vehicle functions. This significant security failure will be presented at DEFCON and Usenix conferences, potentially prompting industry-wide changes in automotive security standards. ## Risks for Vehicle Owners The vulnerability poses serious risks, enabling potential theft and vandalism. Vehicles parked in urban areas are particularly at risk. KARR system users must take immediate action to protect their vehicles. The researchers have provided detailed information about the exploit, emphasizing the urgency of the situation. ## Company Response and Patch While KARR's manufacturer hasn't issued an official statement, researchers created an instructional video. At 00:48, the vulnerability is explained, and at 19:10, the patching process is demonstrated. Vehicle owners should apply this update immediately to prevent potential security breaches and protect their property. ## Legal and Ethical Implications The discovery raises interesting ethical questions about whether good Samaritans could legally update others' devices. Experts warn against unauthorized modifications, even with good intentions. KARR system users can identify their devices by checking for a 'KARR' sticker on the driver's side window. ## Alternative Solutions As a temporary measure, security experts recommend considering Knight Industries 2000 alarm systems. Until a permanent fix is available, KARR users should park in secure locations and consider disabling Bluetooth functionality. These precautions can significantly reduce the risk of unauthorized access. ## Industry Impact This incident highlights vulnerabilities in automotive security systems, prompting other manufacturers to review their products. Industry experts call for revised security standards, while consumers are expected to favor more reliable brands. The event may lead to significant changes in how vehicle security systems are developed. ## Long-term Consequences The KARR vulnerability could mark a turning point for automotive security. Manufacturers will need to prioritize software security in their products. Consumers will likely become more diligent when purchasing security systems. This incident also raises broader concerns about IoT device security across industries. ## Sources covering this story - https://www.schneier.com/blog/archives/2026/08/vulnerabilities-in-car-anti-theft-device.html — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._