Embedded Linux Conference 2013 - KEYNOTE Code Sweat: Embed with Nightmares

### Overview In this keynote address from Embedded Linux Conference 2013, an engineering manager from Intel working on the Yocto Project reflects on the history of computer security and outlines the emerging security and privacy threats facing embedded Linux and Internet of Things (IoT) devices. Recounting historical incidents such as an internal 1988 virus incident at Sequent Computer Systems and the concurrent release of the Morris worm, the speaker emphasizes that modern inexpensive embedded systems now possess computing power comparable to past minicomputers (such as the VAX 11/750). As embedded devices become ubiquitous across critical infrastructure, the dangerous assumption that embedded systems are single-purpose and immune to attack leaves them highly vulnerable.

### Key Topics - **History and Evolution of Exploits:** The presentation compares early computing environments and virus behavior (e.g., infectors inserting themselves into `a.out` headers) with modern sophisticated threats such as Stuxnet, which leveraged zero-day exploits across air gaps to target industrial centrifuges. - **Vulnerabilities in Critical Infrastructure:** Examples are highlighted where networked embedded systems lack adequate hardening, including internet-exposed power plant control panels and utility smart grid sensors prone to tampering. - **Zero-Days and Linux Kernel CVEs:** The speaker notes that the Linux kernel averages roughly 2.5 CVEs per week, illustrating that widespread use and open code require continuous patching rather than assumptions of inherent safety. - **Yocto Project Security Initiatives:** How the Yocto Project aims to standardize embedded Linux tooling and provide integrated security layers, robust update systems, vulnerability scanners, and hardware-backed attestation.

### Technical Details - **Software Updates:** Addressing the average 2.5 kernel CVEs per week requires reliable update mechanisms that do not brick systems. The Yocto Project supports package managers (RPM, DEB, OPKG) and is integrating a new updater from Arjan van de Ven's Fenris project (linux-fenris.org). Firmware updating below the kernel remains a hardware-dependent challenge, though UEFI is being explored. - **Access Control & System Hardening:** A dedicated SELinux layer contributed by Wind River (maintained by Mark Hatley and team) provides least-privilege enforcement to minimize root privilege abuse. The project is also investigating Bastille Linux for scanning default misconfigurations, blank passwords, and backdoors, with plans to integrate forensics and footprint analysis into the Web Hob interface. - **Compiler & Toolchain Protections:** Toolchain armoring was explored to generate more resilient binaries, though integration challenges were encountered with EGLIBC. - **Hardware-Enforced Integrity (TXT and TPM):** Intel Trusted Execution Technology (TXT) and the open-source `tboot` project (also used by Fedora, Ubuntu, and SUSE) facilitate measured launches of operating systems or Virtual Machine Monitors (VMMs). Cryptographic hashes are compared against known-good baselines in the TPM. If a mismatch is detected, systems can enter backup or lockdown modes. An open-source remote attestation stack allows enterprise centralized verification of connected device fleets.

### Takeaways The speaker stresses that embedded developers and community members must abandon the misconception that embedded devices do not need serious security engineering. To prevent critical infrastructure failures and protect human safety, the open-source community, silicon vendors, OSVs, and device manufacturers must collaborate on standardized update mechanisms, system hardening, and hardware-rooted attestation through efforts like the Yocto Project.