Ubuntu 26.04.1: what changed, when to upgrade

Ubuntu 26.04.1 in short

Ubuntu 26.04.1 LTS (long-term support) was released on 27 August 2026, four months after Ubuntu 26.04 LTS shipped on 23 April 2026. It is a roll-up of the existing release: the same Linux 7.0 kernel and the same package set, with every stable release update (SRU) and security update published up to 25 August 2026 built into fresh install media. A 26.04 server that has been running apt full-upgrade already has everything in it. A 24.04 LTS server is the one this release matters for, because the first point release is when Canonical opens the upgrade path from the previous LTS. That path opened on 29 September 2026, and one public text file lets you confirm it from your own terminal.

What a .1 point release is

A point release is a snapshot. Canonical takes the 26.04 archive as it stands, with all the updates that have landed in resolute-updates and resolute-security since April, and builds new ISO and cloud images from it. The release announcement puts it in one sentence: "This point release includes many updates and updated installation media has been provided, so that fewer updates will need to be downloaded after installation." Nothing changes about support. The five years still count from April 2026, so 26.04.1 is supported until April 2031, exactly like the April image. The general mechanics, including why later point releases carry a newer kernel and this one does not, are in how Ubuntu point releases work. What follows is specific to 26.04.1.

What changed in Ubuntu 26.04.1

The official 26.04.1 release notes page has the summary. It covers only packages in main and restricted, and the individual package changelogs carry the full details. It is long, and most of it is desktop and laptop hardware. Below are the entries that matter on a server.

Kernel: still Linux 7.0, no newer HWE kernel yet

26.04 LTS shipped with Linux 7.0, up from 6.8 in 24.04. The .1 release stays on 7.0. The notes list several linux SRU builds under the kernel section (the 7.0.0-15.15 tracker among them), so uname -r on a patched machine shows a higher ABI (application binary interface) number than the April image, but the same 7.0 series. The HWE (hardware enablement) metapackages already exist in the 26.04 archive: linux-generic-hwe-26.04 is published, but as of 10 October 2026 it installs a 7.0 kernel, the same series as the GA kernel. GA means general availability, the kernel the release launched with. So there is no newer HWE kernel in 26.04.1, only the package that will carry one when a later point release moves the HWE stack. For 24.04 and earlier, Ubuntu's HWE kernel reference says "Server installations will default to the general availability (GA) kernel and provide the HWE kernel as an option." The 26.04 installer changes one part of that. Subiquity's 26.04 release notes say a matching OEM or HWE metapackage, previously installed by default only on Desktop, "will also be installed for Ubuntu Server" starting with 26.04, when the installer finds one that matches the hardware. A server installed from 26.04 media can therefore end up tracking an HWE package, and dpkg -l | grep hwe shows whether yours does. On a VPS that tracks the GA linux-generic kernel you stay on 7.0 for the life of the release unless you choose otherwise, and whether a server should take the HWE kernel at all is a separate decision you do not need to make today.

One kernel fix is worth naming. Bug 2158267, "Performance regression causes SDXL inference slowdown (~42x)", was fixed in the generic kernel and most cloud flavours. If you run inference workloads on 26.04 and saw them slow down after a kernel update, that is the entry to read.

Server and cloud fixes

• openssl: a security update for the "HollowByte Denial of Service issue" (bug 2161371).
• rsync: "Regression fixes from May 2026 security update" (bug 2155874). If rsync broke for you in May, .1 media carries the fix.
• exim4: three security updates, including a one-byte write into a freed buffer and an information disclosure in PROXYv2.
• ca-certificates: the Mozilla certificate authority bundle moved to version 2.86.
• systemd: a delay in cloud-init caused by a systemd-networkd resolve hook is fixed (bug 2148619), and the core now opens its netfilter socket only when needed.
• libvirt and qemu: a fix for "excessive memory allocation when physical_package_id is large", and a fix for a race between iothreads and throttle groups.
• apparmor: a new upstream release, plus a profile fix for "uucore locales reads". uucore is the shared code under rust-coreutils, and this fix belongs to the same story that held back the 24.04 upgrade prompt until 29 September, covered below.
• ubuntu-meta: pollinate was removed from the cloud-minimal, server, server-minimal and server-raspi seeds, and curl was added explicitly to cloud-minimal and server-minimal. Both changes apply to what a fresh install from .1 media contains.
• debootstrap: "Detect and support SHA512 in Release index files", which matters if you build chroots or containers from the 26.04 archive.
• base-files: /etc/os-release now reads 26.04.1, and the earlier "missing LTS in VERSION" bug is fixed, so the string reads 26.04.1 LTS (Resolute Raccoon).

Installer media

The new ISOs carry four livecd-rootfs fixes. The one a VPS user may meet is "fix: update nocloud password data format" (bug 2149891), which affects unattended installs that pass a password through the NoCloud datasource. The others set kernel and initrd permissions in the casper directory to 0644 and correct two riscv64 boot options. On a provider image you rarely install from ISO, so the practical effect is that a template built from 26.04.1 boots with the security updates through 25 August 2026 already applied.

The release upgrader

Five ubuntu-release-upgrader entries are in .1, and one of them affects every 26.04 machine. Bug 2154602, "data/release-upgrades: set Prompt=lts for resolute", fixed a mistake in the April release: /etc/update-manager/release-upgrades shipped with Prompt=normal, which is the interim-release setting. Version 1:26.04.22 sets it to Prompt=lts. Without that fix, a 26.04 server would be offered 26.10 in October. The others are quirks for the 24.04 path ("mark libfile-libmagic-perl for install on Noble"), a Raspberry Pi quirk, a lint cleanup, and a refreshed mirror list.

How a 26.04 server reaches 26.04.1

There is no upgrade to run. The point release is the archive state, and your server tracks the archive through apt. Two commands bring a 26.04 install to the same state as the .1 media, or past it, with one exception covered below.

sudo apt update
sudo apt full-upgrade

Use full-upgrade rather than upgrade. apt upgrade refuses to remove anything, so when a package update needs an old package gone it prints The following packages have been kept back and leaves them at the old version. full-upgrade is allowed to remove, so it finishes the job. The exception is phasing, which neither command overrides. Ubuntu rolls some updates out to a growing percentage of machines, and the apt_preferences manual says that on a machine outside that percentage the new version "is pinned to 1, and thus held back" until the rollout reaches it. A package held for phasing is not a fault, and a later apt full-upgrade installs it. Check the version string afterwards.

grep VERSION= /etc/os-release

You should see VERSION="26.04.1 LTS (Resolute Raccoon)". If the string still lacks the .1, the base-files update has not been applied, which usually means apt update failed against your mirror. Read the output of apt update again. A mirror that has not synced yet is the common cause on a fresh provider image.

Next, find out whether the kernel moved.

cat /var/run/reboot-required
uname -r

*** System restart required *** means a package that needs a reboot was installed, and on a server that is almost always the kernel. uname -r shows the kernel that is running now. The new one is not active until you reboot, so reboot when you can afford a minute of downtime. If the machine does not come back, a VPS that stops booting after a kernel update almost always boots on the previous kernel from the GRUB menu. Once it is up on the new kernel, sudo apt autoremove --purge clears the old ones, and cleaning up old kernels on Ubuntu covers what to keep.

Last, confirm the upgrader fix landed.

grep -v '^#' /etc/update-manager/release-upgrades

You should see Prompt=lts. If you see Prompt=normal, you or a provisioning script edited that file before .1, so dpkg kept your copy instead of installing the new one. Set it to lts by hand. The difference decides whether your server is offered 26.10 this October or the next LTS in 2028, and why a server should stay on LTS releases covers the reasoning.

Why a 24.04 server still says there is nothing to upgrade to

Since 29 September 2026 it should not. For the month between the 26.04.1 release and that date, 26.04.1 existed and the upgrader still said no, which confused a lot of people. The reason was one flag in one text file that Canonical controls, and the same file is the first thing to check if a 24.04 server still says no today.

On a 24.04 server, /etc/update-manager/release-upgrades holds Prompt=lts. With that setting, do-release-upgrade downloads https://changelogs.ubuntu.com/meta-release-lts and reads the list of releases in it. For each release newer than yours, it checks a Supported: field. The relevant loop in update-manager's MetaRelease.py, trimmed:

for dist in dists:
    if dist.date > current_dist.date:
        if not dist.supported and not self.useDevelopmentRelease:
            continue
        upgradable_to = dist
        break

A release with Supported: 0 is skipped as if it did not exist. You can read the file yourself.

curl -s https://changelogs.ubuntu.com/meta-release-lts | grep -A4 '^Dist: resolute'

As of 10 October 2026 it prints this:

Dist: resolute
Name: Resolute Raccoon
Version: 26.04.1 LTS
Date: Thu, 23 April 2026 00:26:04 UTC
Supported: 1

The block also carries an UpgradeTool line pointing at the resolute upgrader in resolute-updates. Until 29 September the Version line already said 26.04.1, but Supported read 0. With that value the loop found no upgradable release, new_dist stayed empty, and do-release-upgrade printed the message written for the Prompt=lts case:

Checking for a new Ubuntu release
There is no development version of an LTS available.
To upgrade to the latest non-LTS development release
set Prompt=normal in /etc/update-manager/release-upgrades.

If your 24.04 server prints that today, the flag is no longer the reason. Run the curl line and confirm it shows Supported: 1, check that /etc/update-manager/release-upgrades still says Prompt=lts and not Prompt=never, and run the command again. Ignore the hint about Prompt=normal. That setting makes the upgrader read the full release list and keeps the machine on the interim-release track, so once it reaches 26.04 it would be offered 26.10, a release with nine months of support. The shorter No new release found. message is the same condition on a machine whose file already says Prompt=normal, and what to do when do-release-upgrade finds no new release goes through both messages and their other causes. One more message is worth knowing. Please install all available updates for your release before upgrading. means you have pending updates on 24.04, and the fix is sudo apt full-upgrade before you try again.

Why did the flag stay at 0 for a month? The 26.04.1 announcement said: "Users of Ubuntu 24.04 LTS will be offered an automatic upgrade to 26.04.1 LTS via Update Manager a couple of weeks following this release after some planned backports to address regressions in a recent version of rust-coreutils." 26.04 is the first LTS where ls and the other core utilities come from rust-coreutils instead of GNU coreutils, and what the Rust rewrites in Ubuntu's base system change explains why an upgrade from 24.04 is where a regression in them appears first. Canonical held the path until 29 September 2026, when the release team announced: "Upgrades from Ubuntu 24.04 LTS to Ubuntu 26.04.1 LTS, codenamed 'Resolute Raccoon', are now enabled." The file changed to Supported: 1. Desktop users are "offered an automatic upgrade to 26.04.1 LTS via Update Manager, rolled out progressively over the coming days". Server users do not wait for that rollout: the announcement says they can "start the upgrade at any time by running: $ do-release-upgrade". Once its periodic release check has run, the SSH login banner on 24.04 shows New release '26.04.1 LTS' available. followed by Run 'do-release-upgrade' to upgrade to it., and the same command that said no in September now offers 26.04.1 with no change on your side.

If you do not want to wait

There is no longer anything to wait for. Before 29 September the 26.04.1 announcement named a way around the flag: do-release-upgrade -d. The flag's help text reads "If using the latest supported release, upgrade to the development release", which sounds like 26.10 but is not, on an LTS. With Prompt=lts, -d does two things in the code above. It appends -development to the URL, so the upgrader reads meta-release-lts-development, and it sets useDevelopmentRelease, which is the second half of the continue condition. The Supported: 0 skip no longer applied, and resolute was offered. Now that the flag reads 1, that shortcut is unnecessary. The plain command offers 26.04.1, and it is the one Canonical's 29 September announcement gives server users.

sudo do-release-upgrade

If you upgraded early with -d, you are on the same release as everyone else, and sudo apt full-upgrade on 26.04 brings you up to date with everything published since. Either way, take a snapshot first, and read the full 24.04 to 26.04 upgrade walkthrough for the SSH port 1022 fallback and the third-party repository handling. If the upgrade stops halfway, recovering a failed Ubuntu release upgrade is the page to have open.

The decision

Already on 26.04: nothing special to do. Run sudo apt update && sudo apt full-upgrade and reboot if /var/run/reboot-required exists. Then confirm Prompt=lts. You were never behind, because the point release is the update stream you were already on.

On 24.04: the upgrade path is open. Canonical enabled it on 29 September 2026, and as of 10 October 2026 the curl line above shows Supported: 1. Take a snapshot, run sudo apt full-upgrade so nothing is pending, then run sudo do-release-upgrade. 24.04 LTS itself is supported until April 2029, so you can pick a quiet maintenance window rather than rushing, but there is no flag left to wait for.

On 22.04 or an interim release: the release notes are explicit that "you must first upgrade to either Ubuntu 24.04 LTS or 25.10 before you can proceed to 26.04 LTS". Go to 24.04 first, then follow the 24.04 path above. For a 22.04 server, the two-hop route from 22.04 to 26.04 through 24.04 covers the check and snapshot to take between the hops, and the PPA, PHP, Python, database and netplan breaks to expect along the way.

FAQ

Is Ubuntu 26.04.1 a new version I need to install?

No. Ubuntu 26.04.1 LTS, released on 27 August 2026, is the 26.04 archive with four months of updates built into new install media. A 26.04 server that runs sudo apt update && sudo apt full-upgrade is at or past the .1 state, apart from any update still phasing in, and grep VERSION= /etc/os-release shows 26.04.1 LTS (Resolute Raccoon) once the base-files update is applied. Support still ends in April 2031, counted from the April 2026 release.

Why does do-release-upgrade on 24.04 say there is no development version of an LTS available?

Until 29 September 2026 it said that because Prompt=lts makes the upgrader read meta-release-lts, and that file listed 26.04.1 with Supported: 0. The upgrader skips unsupported entries, found nothing newer, and printed the message written for the Prompt=lts case. Canonical flipped the flag to Supported: 1 when it enabled the upgrade path on 29 September 2026. If you still see the message, confirm the curl check shows Supported: 1 and that Prompt=lts is set, then try again. Do not set Prompt=normal; it puts the server on the interim-release track.

Does 26.04.1 include a new kernel?

No. 26.04.1 stays on the Linux 7.0 series that 26.04 LTS shipped with, updated through several SRU builds. The HWE metapackages such as linux-generic-hwe-26.04 already exist, but they currently install the same 7.0 series as the GA kernel. A newer HWE kernel arrives with a later point release, .2 by Ubuntu's usual pattern. Since 26.04, the server installer also installs a matching OEM or HWE metapackage when it finds one for the hardware. A VPS that tracks linux-generic keeps 7.0 unless you opt into the HWE stack yourself.

Should I use do-release-upgrade -d to move from 24.04 now?

Not any more. Before 29 September 2026 the announcement offered -d for anyone who did not want to wait, because -d with Prompt=lts reads the LTS development list and ignores the Supported: 0 flag. The flag now reads 1, so plain sudo do-release-upgrade offers 26.04.1, and that is the command Canonical's 29 September announcement gives server users. Take a snapshot first either way.