Elect new IC/GuestOS revision (commit 661a980)

Release Notes for release-2026-10-16_03-29-base (661a9806c9eef7106475c396e6348fba63e74066) This release is based on changes since release-2026-10-08_03-33-base (4a0dbb9251df6da0b65ab7a4d35e9a9871f58510).

Please note that some commits may be excluded from this release if they're not relevant, or not modifying the GuestOS 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:

• 7546892ba Core Protocol: all-in-one nodes for cloud engines (#11349)
• c2668f10d Core Protocol(http-handler): add histogram of validated sender_info sizes (#11846)
• 88183ca61 Core Protocol(execution): reserve storage cycles based on the subnet memory saturation when a DTS execution finishes (#11853)
• 5923ac991 Core Protocol(execution): allow subnet admins of cloud engines every access validated by validate_sender (#11835)
• 3abf5fcfa Core Protocol(p2p): reassemble blocks whose canister HTTP responses were stripped (#11718)
• 822e08b8f Core Protocol(cup_explorer): extract the threshold master public keys of a CUP (#11786)
• 0e0e15dbf Core Protocol: use CupType::SubnetSplitting also for destination subnet (#11759)
• b02df10a2 Core Protocol(p2p): serve canister HTTP responses out of a block (#11717)
• 8d8880f07 Core Protocol: report monotonic consumed cycles in the replicated_state_consumed_cycles_since_replica_started gauge (#11785)
• d631361ee Core Protocol: use the monotonic consumed cycles of deleted canisters (#11782)

Bugfixes:

• aeb1a02de Core Protocol: deflake //rs/tests/consensus/backup:backup_manager_upgrade_test_head_nns_local (#11844)
• b011bba89 Core Protocol(execution): only log "[DTS] Finished response callback" for DTS executions (#11838)
• 50d5ce0bf Core Protocol: Reorder instrumentation (#11836)
• 649156c2b Core Protocol: deflake //rs/tests/consensus/subnet_recovery:sr_app_no_upgrade_enable_chain_keys_test_farm_colocate (#11818)
• 30c09fe40 Core Protocol: deflake //rs/tests/consensus:replica_determinism_test_local by not asserting that a state sync checkpoint still has its unverified marker (#11805)
• 0c50f88dc Core Protocol: deflake //rs/tests/nns:delete_subnet_test_local (#11803)
• f81fead72 Core Protocol: cap slice instructions executed at the message instructions left (#11798)
• 7975589f1 Node: Cleanup a little from #11658 (#11845)
• c570da49f Node: deflake //rs/tests/consensus/upgrade:upgrade_downgrade_old_nns_subnet_test_head_nns_farm_colocate (#11856)

Performance improvements:

• bfddc1ae3 Core Protocol: avoid cloning when calling hex::encode (#11839)

Chores:

• 3dc8fc11b Core Protocol(deps): bump vulnerable rust packages (rustls, hickory-resolver) (#11828)
• f92eebb04 Core Protocol: drop SubnetMetrics::consumed_cycles_{http,ecdsa}_outcalls (#11783)
• 661a9806c Node: Update Base Image Refs [2026-10-15-0806] (#11861)
• 53241a4c3 Node: Ensure guest_vm_type is reasonable (#11651)
• 46bc78d90 Node: Fix a few more small things across ICOS (#11658)
• 1b4cc653e Node: Update Base Image Refs [2026-10-08-0808] (#11787)

Refactoring:

• 86a3be485 Core Protocol(execution): report the role of the canister in CanisterInvalidController (#11842)
• b4045ef85 Core Protocol(execution): validate private custom sections and snapshots of other canisters in validate_sender (#11832)
• 8002cc155 Core Protocol(execution): validate the install_chunked_code store canister via a dedicated CanisterAccess variant (#11829)
• bd3e1541d Core Protocol(execution): centralize management canister access control in validate_sender (#11788)

Tests:

Documentation:

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

IC-OS Verification

To build and verify the IC-OS GuestOS 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/661a9806c9eef7106475c396e6348fba63e74066/ci/scripts/repro-check | python3 - -c 661a9806c9eef7106475c396e6348fba63e74066 --guestos

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 GuestOS version here, you have the option to verify the build reproducibility of the HostOS by passing --hostos to the script above instead of --guestos, or the SetupOS by passing --setupos.