Release Notes for [release-2026-10-16_03-29-base](https://github.com/dfinity/ic/tree/release-2026-10-16_03-29-base) (`661a9806c9eef7106475c396e6348fba63e74066`)
This release is based on changes since [release-2026-10-08_03-33-base](https://dashboard.internetcomputer.org/release/4a0dbb9251df6da0b65ab7a4d35e9a9871f58510) (`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](https://github.com/dfinity/ic/compare/release-2026-10-08_03-33-base...release-2026-10-16_03-29-base).
## Features:
* [`7546892ba`](https://github.com/dfinity/ic/commit/7546892ba) Core Protocol: all-in-one nodes for cloud engines ([#11349](https://github.com/dfinity/ic/pull/11349))
* [`c2668f10d`](https://github.com/dfinity/ic/commit/c2668f10d) Core Protocol(http-handler): add histogram of validated sender_info sizes ([#11846](https://github.com/dfinity/ic/pull/11846))
* [`88183ca61`](https://github.com/dfinity/ic/commit/88183ca61) Core Protocol(execution): reserve storage cycles based on the subnet memory saturation when a DTS execution finishes ([#11853](https://github.com/dfinity/ic/pull/11853))
* [`5923ac991`](https://github.com/dfinity/ic/commit/5923ac991) Core Protocol(execution): allow subnet admins of cloud engines every access validated by validate_sender ([#11835](https://github.com/dfinity/ic/pull/11835))
* [`3abf5fcfa`](https://github.com/dfinity/ic/commit/3abf5fcfa) Core Protocol(p2p): reassemble blocks whose canister HTTP responses were stripped ([#11718](https://github.com/dfinity/ic/pull/11718))
* [`822e08b8f`](https://github.com/dfinity/ic/commit/822e08b8f) Core Protocol(cup_explorer): extract the threshold master public keys of a CUP ([#11786](https://github.com/dfinity/ic/pull/11786))
* [`0e0e15dbf`](https://github.com/dfinity/ic/commit/0e0e15dbf) Core Protocol: use `CupType::SubnetSplitting` also for destination subnet ([#11759](https://github.com/dfinity/ic/pull/11759))
* [`b02df10a2`](https://github.com/dfinity/ic/commit/b02df10a2) Core Protocol(p2p): serve canister HTTP responses out of a block ([#11717](https://github.com/dfinity/ic/pull/11717))
* [`8d8880f07`](https://github.com/dfinity/ic/commit/8d8880f07) Core Protocol: report monotonic consumed cycles in the replicated_state_consumed_cycles_since_replica_started gauge ([#11785](https://github.com/dfinity/ic/pull/11785))
* [`d631361ee`](https://github.com/dfinity/ic/commit/d631361ee) Core Protocol: use the monotonic consumed cycles of deleted canisters ([#11782](https://github.com/dfinity/ic/pull/11782))
## Bugfixes:
* [`aeb1a02de`](https://github.com/dfinity/ic/commit/aeb1a02de) Core Protocol: deflake //rs/tests/consensus/backup:backup_manager_upgrade_test_head_nns_local ([#11844](https://github.com/dfinity/ic/pull/11844))
* [`b011bba89`](https://github.com/dfinity/ic/commit/b011bba89) Core Protocol(execution): only log "[DTS] Finished response callback" for DTS executions ([#11838](https://github.com/dfinity/ic/pull/11838))
* [`50d5ce0bf`](https://github.com/dfinity/ic/commit/50d5ce0bf) Core Protocol: Reorder instrumentation ([#11836](https://github.com/dfinity/ic/pull/11836))
* [`649156c2b`](https://github.com/dfinity/ic/commit/649156c2b) Core Protocol: deflake //rs/tests/consensus/subnet_recovery:sr_app_no_upgrade_enable_chain_keys_test_farm_colocate ([#11818](https://github.com/dfinity/ic/pull/11818))
* [`30c09fe40`](https://github.com/dfinity/ic/commit/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](https://github.com/dfinity/ic/pull/11805))
* [`0c50f88dc`](https://github.com/dfinity/ic/commit/0c50f88dc) Core Protocol: deflake //rs/tests/nns:delete_subnet_test_local ([#11803](https://github.com/dfinity/ic/pull/11803))
* [`f81fead72`](https://github.com/dfinity/ic/commit/f81fead72) Core Protocol: cap slice instructions executed at the message instructions left ([#11798](https://github.com/dfinity/ic/pull/11798))
* [`7975589f1`](https://github.com/dfinity/ic/commit/7975589f1) Node: Cleanup a little from #11658 ([#11845](https://github.com/dfinity/ic/pull/11845))
* [`c570da49f`](https://github.com/dfinity/ic/commit/c570da49f) Node: deflake //rs/tests/consensus/upgrade:upgrade_downgrade_old_nns_subnet_test_head_nns_farm_colocate ([#11856](https://github.com/dfinity/ic/pull/11856))
## Performance improvements:
* [`bfddc1ae3`](https://github.com/dfinity/ic/commit/bfddc1ae3) Core Protocol: avoid cloning when calling `hex::encode` ([#11839](https://github.com/dfinity/ic/pull/11839))
## Chores:
* [`3dc8fc11b`](https://github.com/dfinity/ic/commit/3dc8fc11b) Core Protocol(deps): bump vulnerable rust packages (rustls, hickory-resolver) ([#11828](https://github.com/dfinity/ic/pull/11828))
* [`f92eebb04`](https://github.com/dfinity/ic/commit/f92eebb04) Core Protocol: drop SubnetMetrics::consumed_cycles_{http,ecdsa}_outcalls ([#11783](https://github.com/dfinity/ic/pull/11783))
* [`661a9806c`](https://github.com/dfinity/ic/commit/661a9806c) Node: Update Base Image Refs [2026-10-15-0806] ([#11861](https://github.com/dfinity/ic/pull/11861))
* [`53241a4c3`](https://github.com/dfinity/ic/commit/53241a4c3) Node: Ensure guest_vm_type is reasonable ([#11651](https://github.com/dfinity/ic/pull/11651))
* [`46bc78d90`](https://github.com/dfinity/ic/commit/46bc78d90) Node: Fix a few more small things across ICOS ([#11658](https://github.com/dfinity/ic/pull/11658))
* [`1b4cc653e`](https://github.com/dfinity/ic/commit/1b4cc653e) Node: Update Base Image Refs [2026-10-08-0808] ([#11787](https://github.com/dfinity/ic/pull/11787))
## Refactoring:
* [`86a3be485`](https://github.com/dfinity/ic/commit/86a3be485) Core Protocol(execution): report the role of the canister in CanisterInvalidController ([#11842](https://github.com/dfinity/ic/pull/11842))
* [`b4045ef85`](https://github.com/dfinity/ic/commit/b4045ef85) Core Protocol(execution): validate private custom sections and snapshots of other canisters in validate_sender ([#11832](https://github.com/dfinity/ic/pull/11832))
* [`8002cc155`](https://github.com/dfinity/ic/commit/8002cc155) Core Protocol(execution): validate the install_chunked_code store canister via a dedicated CanisterAccess variant ([#11829](https://github.com/dfinity/ic/pull/11829))
* [`bd3e1541d`](https://github.com/dfinity/ic/commit/bd3e1541d) Core Protocol(execution): centralize management canister access control in validate_sender ([#11788](https://github.com/dfinity/ic/pull/11788))
## Tests:
## Documentation:
Full list of changes (including the ones that are not relevant to GuestOS) can be found on [GitHub](https://github.com/dfinity/dre/blob/44acae76432a0acc6afb230653bc649b0cca5820/replica-releases/661a9806c9eef7106475c396e6348fba63e74066.md).

# 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`.
