Ubuntu 25.10 introduces Rust-based sudo for improved security features

Now, Rust might seem like just another buzzword if you’ve been ignoring all the noise about how safe and modern it is, but the switch from C to Rust with sudo isn’t just about trendy programming languages or security posturing. It’s about rethinking a tool that’s basically glued into every admin's workflow, and there are real-world implications for stability and safety here. Maybe you’re already thinking, “Okay, do I need to worry about compatibility or some weird quirks popping up?” It's a legitimate question, and we’ll dive into that. But for now, let’s just say this move is worth your attention, even if you’re skeptical of change—or just already tired of typing "sudo" for the thousandth time today.

Why Switch to Rust?

First things first: you’re probably wondering why Canonical suddenly decided to rewrite a tool that has been rock-solid (for the most part) for decades. The short answer: security.

Rust, unlike C, is built with memory safety baked into its DNA. If you’ve ever stayed up late patching a vulnerability caused by things like buffer overflows or use-after-free bugs, you’ll appreciate what this means. Rust doesn’t let those mistakes happen in the first place—it’s like having a safety net you don’t even notice is there until something tries to go horribly wrong.

This change isn’t about jumping on the “modern programming language” bandwagon. It’s a deliberate move to reduce security headaches across the board. Rust is smart. It scans for nasties at compile time—so by the time code is running on your system, the odds of low-level bugs being exploitable drop dramatically. And frankly, tools like sudo—which basically hold the keys to the kingdom for elevating permissions—can’t afford to be anything less than airtight.

Will Anything Actually Change for You?

Here’s the good news: if you already know how to use sudo, there’s nothing new to learn. The syntax? Exactly the same. Whether you’re enabling admin rights with a quick sudo apt update or doing something gnarly like a one-liner shell escape, the core functionality doesn’t change. This isn’t some massive shakeup that’ll force you to rewrite all your scripts or rethink your workflows.

But, and this is important—sudo-rs isn’t aimed at being a 1:1 replacement. It’s taking a “less is more” approach. Some obscure features from the original sudo have been culled. Don’t panic just yet; Canonical’s keeping the legacy C-based sudo available in the archives for anyone who’s dependent on some niche functionality. If you’ve got custom systems using funky sudo configurations, you’ll want to test things out before you jump in headfirst.

Security Features Admins Will Appreciate

Let’s talk about the stuff sudo-rs brings to the table that might make life a little easier—or at least harder for attackers.

First off, there’s the reduced attack surface. Rust’s memory safety features mean vectors like memory misuse, overflows, and dangling pointers are essentially squashed. For a tool that deals directly with privilege escalation, that’s huge. You don’t want something that lets attackers slip through cracks—it should slam the door in their faces.

Then there’s improved NOEXEC support. This will help lock down shell escapes to prevent privilege escalation shenanigans. If you’ve dealt with attackers trying to spawn shells from tools they weren’t supposed to, this feature is your friend.

For anyone deploying AppArmor profiles, sudo-rs integrates like a champ. It’s better aligned with modern application confinement frameworks, which makes it ideal for locking down environments while keeping a closer lid on privileges.

And here’s a nice touch for organizations that are slow to upgrade kernels—sudo-rs supports pre-Linux 5.9 kernels. That’s welcome news for those of us still clinging to older LTS versions like Ubuntu 20.04 for stability reasons.

Things to Watch for

I’ve got to be upfront: no transition is perfect. While sudo-rs looks solid on paper, there are still a few things that might trip folks up:

• Missing Features: Some less obvious functionality from the old sudo didn’t make the cut in sudo-rs. Stuff like sudoreplay (great for auditing command logs) or SELinux support isn’t here yet—and those could be deal-breakers for certain enterprise setups. If you rely on those, hold tight for updates.
• Testing Phase: Canonical’s made it clear they want feedback. This is where you come in. Testing sudo-rs in staging environments could help surface problems before the tool becomes mandatory in Ubuntu 26.04 LTS. Throw it on some non-critical systems and see how it behaves with your workflows.

Frankly, this is one of those situations where the transition might seem invisible—but under the right circumstances, small incompatibilities could jump out when you least expect them (looking at you, 3 a.m. outages). The time to find those snags is before sudo-rs becomes the default.

The Bigger Picture: Rust in Linux System Utilities

As much as this is a technical shift, there’s something symbolic about Canonical putting its weight behind Rust. It’s not just sudo—it’s the beginning of broader Rust adoption in Linux systems programming.

Admins, if you haven’t brushed up on Rust, this might be your nudge to at least learn the basics. You don’t need to become an expert overnight, but knowing your way around tools written in Rust (or debugging them when things go sideways) is going to be increasingly relevant.

I wouldn’t be surprised if we started seeing other distros follow suit. Debian, Fedora, and the like could easily pick up on the trend for critical components. This isn’t limited to sudo—it’s possible that utilities across the stack will shift toward Rust where it makes sense.

What Canonical’s Got Right

Switching to sudo-rs might sound like a big scary deal, but Canonical’s doing a couple of things that make it less daunting for admins:

• Legacy Support: They’re not forcing anyone into the new version cold turkey. If sudo-rs isn’t a perfect fit for your environment yet, the old C-based sudo isn’t disappearing.
• Feedback Window: By targeting Ubuntu 26.04 LTS for sudo-rs adoption, Canonical is giving us plenty of time to test and tweak. LTS versions are long-term commitments; they’re not rushing this transition.

Here’s the kicker, though: most admins probably won’t notice anything dramatically different during their day-to-day operations. This redesign is happening quietly—you won’t see blinking neon signs shouting, “Now in Rust!” It’s designed to be unobtrusive, which, when it comes to a tool like sudo, is exactly what you want. Stability over flashiness.

Our Final Thoughts on This Exciting Transition 

The move to Rust-based sudo isn’t some headline-grabbing gimmick. It’s about hardening one of the most critical pieces of our systems against modern threats while keeping things as seamless as possible for humans like you and me.

Take this chance to test sudo-rs—I’d suggest tossing it onto a few staging boxes running varied workloads. The sooner you uncover quirks or compatibility surprises, the smoother your eventual transition will be.

And hey, maybe this signals the start of something bigger. Rust creeping deeper into the Linux ecosystem isn’t just a technical curiosity—it’s a shift that could reshape system programming standards for years to come. As always, the best approach is to get your hands dirty and see where things land.