Elect new IC/HostOS revision (commit d26cd03)

Release Notes for release-2026-09-25\_03-28-base (d26cd031176beec51b39fbb9e39e80a3a46a748e) ===================================================================================================================================================================

This release is based on changes since release-2026-09-18\_03-28-base (2c2c7c99bd526d8c3da51df32aeeb977e852292d).

Please note that some commits may be excluded from this release if they're not relevant, or not modifying the HostOS image. Additionally, descriptions of some changes might have been slightly modified to fit the release notes format.

To see a full list of commits added since last release, compare the revisions on GitHub.

Features:

• d26cd0311 Core Protocol: Fast upgrades: upgrade permit protocol types (#11548)

Bugfixes:

• 1d7231173 Node(ic-os): make diroid look fakeroot's ownership map up by st\_ino, not d\_ino (#11661)

Chores:

• 847607626 Node: Fix a few small things across ICOS (#11623)
• 8c5304c48 Node: Update Base Image Refs [2026-09-23-0133] (#11657)

Full list of changes (including the ones that are not relevant to HostOS) can be found on GitHub.

IC-OS Verification

To build and verify the IC-OS HostOS disk image, after installing curl if necessary (sudo apt install curl), run:

# From https://github.com/dfinity/ic#verifying-releases
curl -fsSL https://raw.githubusercontent.com/dfinity/ic/d26cd031176beec51b39fbb9e39e80a3a46a748e/ci/scripts/repro-check | python3 - -c d26cd031176beec51b39fbb9e39e80a3a46a748e --hostos

The two SHA256 sums printed above from a) the downloaded CDN image and b) the locally built image, must be identical, and must match the SHA256 from the payload of the NNS proposal.

While not required for this NNS proposal, as we are only electing a new HostOS version here, you have the option to verify the build reproducibility of the GuestOS by passing --guestos to the script above instead of --hostos, or the SetupOS by passing --setupos.