The “upstream first” strategy is only half of the story for embedded devices
A recent blog post by Kees Cook, a Linux security expert and Google security engineer, illustrates the challenges in maintaining the security of the Linux kernel. One of the main takeaways from the blog is: “If you’re not using the latest kernel, you don’t have the most recently added security defenses (including bug fixes).”
Going the “upstream first” route is the absolute best way of keeping the kernel secure. However, it is only part of the story. The challenges faced by device manufacturers running on Linux on embedded devices is vastly different.
Continue reading “The many challenges of Linux OS / BSP security maintenance” »
Monitoring and managing vulnerabilities in embedded Linux devices presents a unique set of needs that traditional IT vulnerability tools fail to address and result in wasted efforts chasing false positives and inefficiencies due to cumbersome workflows. After evaluating multiple IT cybersecurity tools, we at Timesys ended up creating a vulnerability management tool called Vigiles, which is optimized for embedded devices. This blog aims to share the lessons learned and how the right tool can bring your security maintenance cost down while improving the security posture of the device.
Continue reading “Evaluating vulnerability tools for embedded Linux devices” »
With 300+ vulnerabilities being reported weekly in the US National Vulnerability Database (NVD), it is more challenging than ever to maintain the security of open source and third-party software used in embedded system products. One common approach to tackle the problem is to adopt a risk-based vulnerability management strategy in which vulnerabilities that pose the highest risk to your organization are remediated first. This blog outlines how to establish such an process as part of your software development lifecycle while keeping the maintenance cost and risk of exposure low.
Continue reading “Vulnerability management and triaging” »
Qualcomm Snapdragon processors support secure boot which ensures only authenticated software runs on the device. By configuring the processor for secure boot, unauthorized or modified code is prevented from being run. The authenticity of the image is verified by use digital signatures and certificate chain.
Secure Boot process overview
On Qualcomm processors the first piece of software that runs is called Primary BootLoader (PBL) and it resides in immutable read-only-memory (ROM) of the processor. By configuring the processor for secure boot, PBL can verify the authenticity of the Secondary BootLoader (SBL) before executing it. Continue reading “Secure boot on Snapdragon 410” »
Updated on 8/14/2018
Google Project Zero team discovered a method to read privileged memory from user space by utilizing CPU data cache timing to leak information out of mis-speculated execution. Variants of this issue are known to affect many modern processors, including certain processors by Intel, AMD and ARM. For more details refer to this blogpost.
So far, there are three known variants of the issue:
Variants 1 & 2 are referred to as Spectre and Variant 3 as Meltdown.
Timesys has been monitoring vendor websites and open source mailing lists regarding affected CPUs and software mitigation strategies, and below are our findings:
Continue reading “Meltdown and Spectre vulnerabilities” »
This blog aims to introduce the concept of Trusted Execution Environment (TEE) and how end users can leverage open source software to safely deploy applications that require handling confidential information.
Continue reading “Trusted Software Development Using OP-TEE” »
What is secure boot?
Secure boot ensures only authenticated software runs on the device and is achieved by verifying digital signatures of the software prior to executing that code. To achieve secure boot, processor/SoC support is required. In our experience, some of the more secure boot friendly processors with readily available documentation are NXP i.MX/QorIQ Layerscape, Xilinx Zynq, Atmel SAMA5, TI Sitara and Qualcomm Snapdragon series. Some TI Sitara processors (AM335x) might involve TI factory programming of signing keys and custom part numbers.
Continue reading “Secure Boot and Encrypted Data Storage” »
Embedded devices have unique security needs ranging from IP protection, anti-cloning / anti-counterfeit capability, device software integrity, user data protection, securing network communication, device authentication and ability to run only trusted applications. A wide range of open source technologies are available that can help implement the aforementioned security requirements. However, it is not always apparent which mechanisms are best suited for a given use case, resulting in a steep learning curve. This blog series aims to give a high-level overview of the different methods to secure your product and help accelerate your trusted software deployment.
Continue reading “Securing Embedded Linux Devices” »
The Internet of Things (IoT) has quickly led to the deployment of ubiquitous, unattended devices throughout our homes, offices, factories and public spaces. In this continuously expanding connected world of devices and IoT, the need to update/upgrade your product’s software/firmware is a certainty. There is no single software update approach that fits all, but there are key questions you should consider when designing your approach. They are: Why, When, What and How.
Continue reading “Software / Firmware Update Design Considerations” »