(Image: heise medien). Canonical offers IoT Linux Ubuntu Core in version 26 with optimized OTA updates, live kernel patching, and up to 15 years of security updates. The immutable Linux system Ubuntu Core for Internet-of-Things (IoT) and edge devices has been released in version 26. Canonical highlights “precise” Linux builds, optimized OTA updates, live kernel patching, hardware-backed protection, and up to 15 years of security updates [1]. In a blog post, Canonical [2] announces the updated distribution. The improvements to the minimal operating system predestine it for low-latency AI applications and mission-critical deployments. Reduced installation times, reduction of OTA update size by 90 percent, and “precise” builds via Chisel [3] are responsible for this. The focus remains on security, with every component running in a sandbox, snaps cryptographically signed, and the “measured boot chain” allowing only verified software to start. The Long-Term Support release (LTS) also helps to account for the EU’s Cyber Resilience Act (CRA) [4]. For operators of critical infrastructure, Ubuntu Core 26 aims to reduce costs for software updates, maintenance, and installation times. Over-the-Air updates (OTA) are significantly smaller since the improved delta format for Snap reduces the size of snaps by 50 to 90 percent. Updates to the core snaps are to comprise only 1.5 megabytes instead of 16 megabytes. The installations rely on initramfs, which should avoid redundant reboots. “Precise” Builds. Ubuntu’s Chisel build system brings precise composition for the core snaps. It enforces explicit and traceable dependencies, for example. This makes it possible to trace each file in the system back to its origin. This is intended to improve integrity checks and vulnerability analysis. As a distinction, Canonical names builds with Yocto — there, origin and dependencies are mostly only implicitly specified. Chisel also provides a reduction in the size of the base image by seven percent. Ubuntu Core relies on full disk encryption and stores keys with LUKS2 headers in the TPM. Arm Trusted Execution Environments (TEE) are also supported. The security improvements from Ubuntu 26.04 [5] also make their way into Ubuntu Core 26. For example, Livepatch brings the application of security patches to the kernel without reboot to ARM64 architectures as well. Even retroactively officially from Core 20 onward. Canonical promises “zero downtime.” The blog post announcement mentions additional useful features for management in larger networks. Most recently, Ubuntu Core 24 [6] brought major changes to the IoT operating system. (dmk [8]). URL of this article:. https://www.heise.de/-11300222. Links in this article:. https://www.heise.de/news/Ubuntu-Linux-Distribution-liefert-15-Jahre-Support-11080739.html. https://canonical.com/blog/canonical-launches-ubuntu-core-26. https://documentation.ubuntu.com/chisel/latest/. https://www.heise.de/thema/CRA. https://www.heise.de/ratgeber/Linux-Distribution-Ubuntu-Desktop-26-04-LTS-im-Test-11243892.html. https://www.heise.de/news/Ubuntu-Core-24-Canonicals-IoT-Linux-jetzt-mit-Landscape-administrieren-9748573.html. https://pro.heise.de/security/?LPID=39555_HS1L0001_27416_999_0&wt_mc=disp.fd.security-pro.security_pro24.disp.disp.disp. mailto:dmk@heise.de. Copyright © 2026 Heise Medien
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