Ubuntu 26.10 hits beta with a 100% Rust base and the Linux 7.3 kernel
The Ubuntu 26.10 “Stonking Stingray” beta is out: it completes the migration of coreutils to Rust, ships Linux 7.3, GNOME 51, and dbus-broker in place of dbus-daemon. Test it now to gauge the impact on your fleet before the October 15 stable release.
October 1, 2026. Canonical publishes the Ubuntu 26.10 beta, codenamed “Stonking Stingray,” a week later than originally planned. October 1, 2026. The release ships the Linux 7.3 kernel (still a release candidate) and the GNOME 51 desktop, but the real signal lies elsewhere: Ubuntu completes its migration to 100% Rust coreutils. October 1, 2026. The stable release is set for October 15, 2026. Why it matters: removing the C implementations of cp, mv, and rm eliminates, by construction, a whole class of memory-safety bugs in the most heavily used utilities on the system.
The end of a migration begun in 2025
The most structural change in this beta is invisible on screen. Ubuntu finishes switching its coreutils — the shell’s basic utilities — to uutils, their Rust rewrite. As of this release, cp, mv, and rm come from the Rust reimplementation, not the GNU coreutils written in C.
The stakes are security. For decades, C produced buffer overflows, use-after-frees, and memory races in the tools that every script and every user runs constantly. Rust guarantees memory safety at compile time: the bug classes behind most CVEs in native programs become structurally impossible, outside explicit unsafe blocks.
The migration, begun in 2025, comes with a second piece: Rust PGP tools. Ubuntu 26.10 introduces sq, the Sequoia-PGP suite written in Rust, progressively replacing the historic GnuPG tools. The goal is the same — shrink the attack surface of a sensitive cryptographic component by eliminating memory bugs.
For admins, the migration is not purely a security win — it is a compatibility risk too. The Rust implementations aim for GNU-compatible behavior, but edge cases linger: a rarely used flag, a difference in exit codes, or a subtle change in how a command handles a malformed path can break a script that has run unchanged for years. That is exactly why the beta window matters: it is the moment to run your automation against the new utilities before they become the default on every 26.10 install.
The third layer of the base is dbus-broker, which replaces dbus-daemon. This lighter, more modern replacement serves the communication bus between desktop and system processes. Its design trims allocations and improves reliability under load — a quiet but real win for a daemon present in every session.
A Linux 7.3 kernel still in progress
The beta runs on Linux 7.3, a kernel that will not reach a stable release until after October 15 — a deliberate choice for an interim Ubuntu release. The bundled improvements set the tone for the 7.x series:
- a streamlined multi-block allocator for EXT4, speeding up pre-allocation during large downloads;
- zero-copy buffer pools for FUSE over io_uring, reducing memory copies on userspace filesystems;
- a KSM (Kernel Samepage Merging) fix that softens micro-stutters in the UI under heavy memory pressure.
On the graphics driver side, the release jumps to Mesa 26.2 (up from the 26.0.x series in Ubuntu 26.04 LTS), with mesh shaders in NVK, low-latency Vulkan Video encode and decode for AMD via RADV, and Vulkan descriptor heaps enabled by default. The proprietary NVIDIA driver moves to the 615 series.
Low-memory handling changes too: Ubuntu 26.10 lowers the OOM scores of core desktop processes, so the OOM daemon sacrifices applications before the session itself. It is a small but long-awaited fix for anyone who has watched their session get killed at the first memory spike.
GNOME 51 and the day-to-day desktop
GNOME 51 delivers most of the visible changes. It adds a “Reduced Motion” accessibility setting that dials down most animations, simplifies fingerprint enrolment, and reworks the system info panel.
Two additions matter directly for corporate machines. The first is FIDO2/passkey and web-based login (via QR code or URL) on the login and lock screens, alongside existing smartcard support. The second is driver management integrated into the App Center, compensating for the removal of the old Software & Updates tool: the Add-ons > Additional drivers section appears only when a proprietary driver is actually needed.
The Tiling Assistant, one of the preinstalled extensions, gains a Windows-style layout picker: a box slides in from the top of the screen while dragging a window, with layouts on offer. The DING desktop-icons extension is ported to GTK4, aligning context menus and dialogs with the rest of the desktop.
The flavors and the Amd64-v3 image
Ubuntu 26.10 introduces an Amd64-v3 ISO: packages optimized for modern CPUs (recent vector instructions), which only work on recent hardware. It is a way to benefit from new silicon without breaking the generic image’s compatibility.
The official flavors follow: Lubuntu 26.10 with LXQt 2.4.0, Kubuntu 26.10 with KDE Plasma 6.7, and Ubuntu Cinnamon 26.10 with Cinnamon 6.6.2. A generic ARM image and a preinstalled Raspberry Pi image round out the list.
A hardware reporting tool, hwctl, becomes a snap, which illustrates Canonical’s strategy: confine more and more system tools in isolated snaps. It is consistent with the rest of the direction — the distribution pushes security toward isolation and Rust, rather than only fixing things after the fact.
What to test before October 15
The beta is not a finished product, but it is more reliable than a daily snapshot, and Canonical is counting on feedback to freeze the last fixes before October 15. The areas to exercise first are the ones that changed deeply:
- the Rust coreutils migration: verify that scripts and cron jobs relying on precise
cp,mv, orrmbehavior work identically; - the move to dbus-broker: watch services that talk to the bus, especially third-party agents and daemons;
- the Rust PGP tools (
sq): validate existing signing and encryption flows before rolling them out; - graphics drivers: test Mesa 26.2 and NVIDIA 615 on real hardware, especially AMD GPUs with Vulkan Video.
Installing the beta allows an in-place upgrade to stable: apply updates as they arrive and, by October 15, you will be running the same stack as a clean install.
Verdict
If you manage a fleet of Ubuntu desktops, install this beta on a test machine and focus on the Rust coreutils migration and the dbus-broker switch: those are the two changes most likely to break a script or a quiet service. If you run a graphics-heavy workstation, validate Mesa 26.2 and NVIDIA 615 now to avoid surprises on October 15. If you are on servers, the beta is mostly a chance to preview Linux 7.3 and the Rust PGP tools — the rest concerns you less, but the security base alone justifies an evaluation.