Docker Engine version 27 release notes

Release notes
Table of contents

This page describes the latest changes, additions, known issues, and fixes for Docker Engine version 27.

For more information about:

27.4

Release notes for Docker Engine version 27.4 releases.

27.4.1

2024-12-18

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • Fix excessive memory allocations when OTel is not configured. moby/moby#49079
  • The docker info command and the corresponding GET /info API endpoint no longer include warnings when bridge-nf-call-iptables or bridge-nf-call-ip6tables are disabled at the daemon is started. The br_netfilter kernel module is now attempted to be loaded when needed, which made those warnings inaccurate. moby/moby#49090
  • Attempt to load kernel modules, including ip6_tables and br_netfilter when required, using a method that is likely to succeed inside a Docker-in-Docker container. moby/moby#49043
  • Fix a bug that could result in an iptables DOCKER FILTER chain not being cleaned up on failure. moby/moby#49110

Packaging updates

27.4.0

2024-12-09

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

API

  • GET /images/json with the manifests option enabled now preserves the original order in which manifests appeared in the manifest-index. moby/moby#48712

Bug fixes and enhancements

  • When reading logs with the jsonfile or local log drivers, any errors while trying to read or parse underlying log files will cause the rest of the file to be skipped and move to the next log file (if one exists) rather than returning an error to the client and closing the stream. The errors are viewable in the Docker Daemon logs and exported to traces when tracing is configured. moby/moby#48842
  • When reading log files, compressed log files are now only decompressed when needed rather than decompressing all files before starting the log stream. moby/moby#48842
  • Fix an issue that meant published ports from one container on a bridge network were not accessible from another container on the same network with userland-proxy disabled, if the kernel's br_netfilter module was not loaded and enabled. The daemon will now attempt to load the module and enable bridge-nf-call-iptables or bridge-nf-call-ip6tables when creating a network with the userland proxy disabled. moby/moby#48685
  • Fix loading of bridge and br_netfilter kernel modules. moby/moby#48966
  • containerd image store: Fix Docker daemon failing to fully start with a "context deadline exceeded error" with containerd snapshotter and many builds/images. moby/moby#48954
  • containerd image store: Fix partially pulled images not being garbage-collected. moby#48910, moby/moby#48957
  • containerd image store: Fix docker image inspect outputting duplicate references in RepoDigests. moby/moby#48785
  • containerd image store: Fix not being able to connect to some insecure registries in cases where the HTTPS request failed due to a non-TLS related error. moby/moby#48758
  • containerd image store: Remove a confusing warning log when tagging a non-dangling image. moby/moby#49010
  • containerd image store: Do not underline names in docker image ls --tree. docker/cli#5519
  • containerd image store: Change name of USED column in docker image ls --tree to IN USE. docker/cli#5518
  • dockerd-rootless-setuptool.sh install --force now ignores RootlessKit errors moby/moby#48695
  • Disable IPv6 Duplicate Address Detection (DAD) for addresses assigned to the bridges belonging to bridge networks. moby/moby#48684
  • Remove BuildKit init timeout. moby/moby#48963
  • Ignore "dataset does not exist" error when removing dataset on ZFS. moby/moby#48968
  • Client: Prevent idle connections leaking FDs. moby/moby#48764
  • Fix anonymous volumes being created through the --mount option not being marked as anonymous. moby/moby#48755
  • After a daemon restart with live-restore, ensure an iptables jump to the DOCKER-USER chain is placed before other rules. moby/moby#48714
  • Fix a possible memory leak caused by OTel meters. moby/moby#48693
  • Create distinct build history db for each image store. moby/moby#48688
  • Fix an issue that caused excessive memory usage when DNS resolution was made in a tight loop. moby/moby#48840
  • Fix a bug preventing image pulls from being cancelled during docker run. docker/cli#5654
  • The docker login and docker logout command no longer update the configuration file if the credentials didn't change. docker/cli#5569
  • Optimize docker stats to reduce flickering issues. docker/cli#5588, docker/cli#5635
  • Fix inaccessible plugins paths preventing plugins from being detected. docker/cli#5652
  • Add support for events --filter in cobra generated shell completions. docker/cli#5614
  • Fix bash completion for events --filter daemon=. docker/cli#5563
  • Improve shell completion of containers for docker rm. docker/cli#5540
  • Add shell completion for --platform flags. docker/cli#5540
  • rootless: Make /etc/cdi and /var/run/cdi accessible by the Container Device Interface (CDI) integration. moby/moby#49027

Removed

  • Deprecate Daemon.Exists() and Daemon.IsPaused(). These functions are no longer used and will be removed in the next release. moby/moby#48719
  • Deprecate container.ErrNameReserved and container.ErrNameNotReserved. moby/moby#48697
  • Deprecate pkg/platform - this package is only used internally, and will be removed in the next release. moby/moby#48863
  • Deprecate RepositoryInfo.Class. This field is no longer used, and will be removed in the next release. moby/moby#49013
  • Go SDK: Fix deprecation of cli/command.ConfigureAuth(), which was deprecated since v27.2.1. docker/cli#5552
  • Go SDK: Deprecate cli.Errors type in favour of Go's errors.Join docker/cli#5548

Packaging updates

27.3

Release notes for Docker Engine version 27.3 releases.

27.3.1

2024-09-20

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • CLI: Fix issue with command execution metrics not being exported correctly. docker/cli#5457

Packaging updates

27.3.0

2024-09-19

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • containerd image store: Fix docker image prune -a untagging images used by containers started from images referenced by a digested reference. moby/moby#48488
  • Add a --feature flag to the daemon options. moby/moby#48487
  • Updated the handling of the --gpus=0 flag to be consistent with the NVIDIA Container Runtime. moby/moby#48483
  • Support WSL2 mirrored-mode networking's use of interface loopback0 for packets from the Windows host. moby/moby#48514
  • Fix an issue that prevented communication between containers on an IPv4 bridge network when running with --iptables=false, --ip6tables=true (the default), a firewall with a DROP rule for forwarded packets on hosts where the br_netfilter kernel module was not normally loaded. moby/moby#48511
  • CLI: Fix issue where docker volume update command would cause the CLI to panic if no argument/volume was passed. docker/cli#5426
  • CLI: Properly report metrics when run in WSL environment on Windows. docker/cli#5432

Packaging updates

27.2

Release notes for Docker Engine version 27.2 releases.

27.2.1

2024-09-09

Bug fixes and enhancements

  • containerd image store: Fix non-container images being hidden in the docker image ls output. moby/moby#48402
  • containerd image store: Improve docker pull error message when the image platform doesn't match. moby/moby#48415
  • CLI: Fix issue causing docker login to not remove repository names from passed in registry addresses, resulting in credentials being stored under the wrong key. docker/cli#5385
  • CLI: Fix issue that will sometimes cause the browser-login flow to fail if the CLI process is suspended and then resumed while waiting for the user to authenticate. docker/cli#5376
  • CLI: docker login now returns an error instead of hanging if called non-interactively with --password or --password-stdin but without --user. docker/cli#5402

Packaging updates

27.2.0

2024-08-27

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

New

The new features in this release are:

Device code login

This release adds support for using device code login when authenticating to Docker Hub.

You can still use the old method of logging in with a username and password or access token, but device code login is more secure and doesn't require you to enter your password in the CLI.

device-code-login
Device code login

To use the old method, use docker login -u <username>.

Multi-platform support for docker image ls

Experimental

This is experimental and may change at any time without any backward compatibility.

With the containerd image store enabled, the docker image ls command (or docker images shorthand) now supports a --tree flag that now shows if an image is a multi-platform image.

API

  • GET /images/json response now includes Manifests field, which contains information about the sub-manifests included in the image index. This includes things like platform-specific manifests and build attestations.

    The new field will only be populated if the request also sets the manifests query parameter to true.

    Experimental

    This is experimental and may change at any time without any backward compatibility.

Bug fixes and enhancements

  • CLI: Fix issue with remote contexts over SSH where the CLI would allocate a pseudo-TTY when connecting to the remote host, which causes issues in rare situations. docker/cli#5351
  • Fix an issue that prevented network creation with a --ip-range ending on a 64-bit boundary. moby/moby#48326
  • CLI: IPv6 addresses shown by docker ps in port bindings are now bracketed. docker/cli#5365
  • containerd image store: Fix early error exit from docker load in cases where unpacking the image would fail. moby/moby#48376
  • containerd image store: Fix the previous image not being persisted as dangling after docker pull. moby/moby#48380

Packaging updates

Known Issues

  • There is a known issue when authenticating against a registry in the Docker CLI (docker login [registry address]) where, if the provided registry address includes a repository/image name (such as docker login index.docker.io/docker/welcome-to-docker), the repository part (docker/welcome-to-docker) is not normalized and results in credentials being stored incorrectly, which causes subsequent pulls from the registry (docker pull index.docker.io/docker/welcome-to-docker) to not be authenticated. To prevent this, don't include any extraneous suffix in the registry address when running docker login.

    Note

    Using docker login with an address that includes URL path segments is not a documented use case and is considered unsupported. The recommended usage is to specify only a registry hostname, and optionally a port, as the address for docker login.

27.1

Release notes for Docker Engine version 27.1 releases.

27.1.2

2024-08-13

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • Fix a regression that could result in a ResourceExhausted desc = grpc: received message larger than max error when building from a large Dockerfile. moby/moby#48245
  • CLI: Fix docker attach printing a spurious context cancelled error message. docker/cli#5296
  • CLI: Fix docker attach exiting on SIGINT instead of forwarding the signal to the container and waiting for it to exit. docker/cli#5302
  • CLI: Fix --device-read-bps and --device-write-bps options not taking effect. docker/cli#5339
  • CLI: Fix a panic happening in some cases while running a plugin. docker/cli#5337

Packaging updates

27.1.1

2024-07-23

Security

This release contains a fix for CVE-2024-41110 / GHSA-v23v-6jw2-98fq that impacted setups using authorization plugins (AuthZ) for access control. No other changes are included in this release, and this release is otherwise identical for users not using AuthZ plugins.

Packaging updates

27.1.0

2024-07-22

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • rootless: add Requires=dbus.socket to prevent errors when starting the daemon on a cgroup v2 host with systemd moby/moby#48141
  • containerd integration: image tag event is now properly emitted when building images with BuildKit moby/moby#48182
  • CLI: enable shell completion for docker image rm, docker image history, and docker image inspect moby/moby#5261
  • CLI: add and improve shell completions for various flags moby/moby#5261
  • CLI: add OOMScoreAdj to docker service create and docker stack docker/cli#5274
  • CLI: add support for DOCKER_CUSTOM_HEADERS environment variable (experimental) docker/cli#5271
  • CLI: containerd-integration: Fix docker push defaulting the --platform flag to a value of DOCKER_DEFAULT_PLATFORM environment variable on unsupported API versions docker/cli#5248
  • CLI: fix: context cancellation on login prompt docker/cli#5260
  • CLI: fix: wait for the container to exit before closing the stream when sending a termination request to the CLI while attached to a container docker/cli#5250

Deprecated

  • The pkg/rootless/specconv package is deprecated, and will be removed in the next release moby/moby#48185
  • The pkg/containerfs package is deprecated, and will be removed in the next release moby/moby#48185
  • The pkg/directory package is deprecated, and will be removed in the next release moby/moby#48185
  • api/types/system: remove deprecated Info.ExecutionDriver moby/moby#48184

Packaging updates

27.0

Release notes for Docker Engine 27.0.

27.0.3

2024-07-01

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

  • Fix a regression that incorrectly reported a port mapping from a host IPv6 address to an IPv4-only container as an error. moby/moby#48090
  • Fix a regression that caused duplicate subnet allocations when creating networks. moby/moby#48089
  • Fix a regression resulting in fail to register layer: failed to Lchown errors when trying to pull an image with rootless enabled on a system that supports native overlay with user-namespaces. moby/moby#48086

27.0.2

2024-06-27

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

Bug fixes and enhancements

Removed

  • api/types: deprecate ContainerJSONBase.Node field and ContainerNode type. These definitions were used by the standalone ("classic") Swarm API, but never implemented in the Docker Engine itself. moby/moby#48055

27.0.1

2024-06-24

For a full list of pull requests and changes in this release, refer to the relevant GitHub milestones:

New

  • containerd image store: Add --platform flag to docker image push and improve the default behavior when not all platforms of the multi-platform image are available locally. docker/cli#4984, moby/moby#47679
  • Add support to docker stack deploy for driver_opts in a service's networks. docker/cli#5125
  • Consider additional /usr/local/libexec and /usr/libexec paths when looking up the userland proxy binaries by a name with a docker- prefix. moby/moby#47804

Bug fixes and enhancements

  • *client.Client instances are now always safe for concurrent use by multiple goroutines. Previously, this could lead to data races when the WithAPIVersionNegotiation() option is used. moby/moby#47961
  • Fix a bug causing the Docker CLI to leak Unix sockets in $TMPDIR in some cases. docker/cli#5146
  • Don't ignore a custom seccomp profile when used in conjunction with --privileged. moby/moby#47500
  • rootless: overlay2: support native overlay diff when using rootless-mode with Linux kernel version 5.11 and later. moby/moby#47605
  • Fix the StartInterval default value of healthcheck to reflect the documented value of 5s. moby/moby#47799
  • Fix docker save and docker load not ending on the daemon side when the operation was cancelled by the user, for example with Ctrl+C. moby/moby#47629
  • The StartedAt property of containers is now recorded before container startup, guaranteeing that the StartedAt is always before FinishedAt. moby/moby#47003
  • The internal DNS resolver used by Windows containers on Windows now forwards requests to external DNS servers by default. This enables nslookup to resolve external hostnames. This behaviour can be disabled via daemon.json, using "features": { "windows-dns-proxy": false }. The configuration option will be removed in a future release. moby/moby#47826
  • Print a warning when the CLI does not have permissions to read the configuration file. docker/cli#5077
  • Fix a goroutine and file-descriptor leak on container attach. moby/moby#45052
  • Clear the networking state of all stopped or dead containers during daemon start-up. moby/moby#47984
  • Write volume options JSON atomically to avoid "invalid JSON" errors after system crash. moby/moby#48034
  • Allow multiple macvlan networks with the same parent. moby/moby#47318
  • Allow BuildKit to be used on Windows daemons that advertise it. docker/cli#5178

Networking

  • Allow sysctls to be set per-interface during container creation and network connection. moby/moby#47686
    • In a future release, this will be the only way to set per-interface sysctl options. For example, on the command line in a docker run command,--network mynet --sysctl net.ipv4.conf.eth0.log_martians=1 will be rejected. Instead, you must use --network name=mynet,driver-opt=com.docker.network.endpoint.sysctls=net.ipv4.conf.IFNAME.log_martians=1.
IPv6
  • ip6tables is no longer experimental. You may remove the experimental configuration option and continue to use IPv6, if it is not required by any other features.
  • ip6tables is now enabled for Linux bridge networks by default. moby/moby#47747
    • This makes IPv4 and IPv6 behaviors consistent with each other, and reduces the risk that IPv6-enabled containers are inadvertently exposed to the network.
    • There is no impact if you are running Docker Engine with ip6tables enabled (new default).
    • If you are using an IPv6-enabled bridge network without ip6tables, this is likely a breaking change. Only published container ports (-p or --publish) are accessible from outside the Docker bridge network, and outgoing connections masquerade as the host.
    • To restore the behavior of earlier releases, no ip6tables at all, set "ip6tables": false in daemon.json, or use the CLI option --ip6tables=false. Alternatively, leave ip6tables enabled, publish ports, and enable direct routing.
    • With ip6tables enabled, if ip6tables is not functional on your host, Docker Engine will start but it will not be possible to create an IPv6-enabled network.
IPv6 network configuration improvements
  • A Unique Local Address (ULA) base prefix is automatically added to default-address-pools if this parameter wasn't manually configured, or if it contains no IPv6 prefixes. moby/moby#47853
    • Prior to this release, to create an IPv6-enabled network it was necessary to use the --subnet option to specify an IPv6 subnet, or add IPv6 ranges to default-address-pools in daemon.json.
    • Starting in this release, when a bridge network is created with --ipv6 and no IPv6 subnet is defined by those options, an IPv6 Unique Local Address (ULA) base prefix is used.
    • The ULA prefix is derived from the Engine host ID such that it's unique across hosts and over time.
  • IPv6 address pools of any size can now be added to default-address-pools. moby/moby#47768
  • IPv6 can now be enabled by default on all custom bridge networks using "default-network-opts": { "bridge": {"com.docker.network.enable_ipv6": "true"}} in daemon.json, or dockerd --default-network-opt=bridge=com.docker.network.enable_ipv6=trueon the command line. moby/moby#47867
  • Direct routing for IPv6 networks, with ip6tables enabled. moby/moby#47871
    • Added bridge driver option com.docker.network.bridge.gateway_mode_ipv6=<nat|routed>.
    • The default behavior, nat, is unchanged from previous releases running with ip6tables enabled. NAT and masquerading rules are set up for each published container port.
    • When set to routed, no NAT or masquerading rules are configured for published ports. This enables direct IPv6 access to the container, if the host's network can route packets for the container's address to the host. Published ports will be opened in the container's firewall.
    • When a port mapping only applies to routed mode, only addresses 0.0.0.0 or :: are allowed and a host port must not be given.
    • Note that published container ports, in nat or routed mode, are accessible from any remote address if routing is set up in the network, unless the Docker host's firewall has additional restrictions. For example: docker network create --ipv6 -o com.docker.network.bridge.gateway_mode_ipv6=routed mynet.
    • The option com.docker.network.bridge.gateway_mode_ipv4=<nat|routed> is also available, with the same behavior but for IPv4.
  • If firewalld is running on the host, Docker creates policy docker-forwarding to allow forwarding from any zone to the docker zone. This makes it possible to configure a bridge network with a routable IPv6 address, and no NAT or masquerading. moby/moby#47745
  • When a port is published with no host port specified, or a host port range is given, the same port will be allocated for IPv4 and IPv6. moby/moby#47871
    • For example -p 80 will result in the same ephemeral port being allocated for 0.0.0.0 and ::, and -p 8080-8083:80 will pick the same port from the range for both address families.
    • Similarly, ports published to specific addresses will be allocated the same port. For example, -p 127.0.0.1::80 -p '[::1]::80'.
    • If no port is available on all required addresses, container creation will fail.
  • Environment variable DOCKER_ALLOW_IPV6_ON_IPV4_INTERFACE, introduced in release 26.1.1, no longer has any effect. moby/moby#47963
    • If IPv6 could not be disabled on an interface because of a read-only /proc/sys/net, the environment variable allowed the container to start anyway.
    • In this release, if IPv4 cannot be disabled for an interface, IPv6 can be explicitly enabled for the network simply by using --ipv6 when creating it. Other workarounds are to configure the OS to disable IPv6 by default on new interfaces, mount /proc/sys/net read-write, or use a kernel with no IPv6 support.
  • For IPv6-enabled bridge networks, do not attempt to replace the bridge's kernel-assigned link local address with fe80::1. moby/moby#47787

Removed

  • Deprecate experimental GraphDriver plugins. moby/moby#48050, docker/cli#5172
  • pkg/archive: deprecate NewTempArchive and TempArchive. These types were only used in tests and will be removed in the next release. moby/moby#48002
  • pkg/archive: deprecate CanonicalTarNameForPath moby/moby#48001
  • Deprecate pkg/dmesg. This package was no longer used, and will be removed in the next release. moby/moby#47999
  • Deprecate pkg/stringid.ValidateID and pkg/stringid.IsShortID moby/moby#47995
  • runconfig: deprecate SetDefaultNetModeIfBlank and move ContainerConfigWrapper to api/types/container moby/moby#48007
  • runconfig: deprecate DefaultDaemonNetworkMode and move to daemon/network moby/moby#48008
  • runconfig: deprecate opts.ConvertKVStringsToMap. This utility is no longer used, and will be removed in the next release. moby/moby#48016
  • runconfig: deprecate IsPreDefinedNetwork. moby/moby#48011

API

  • containerd image store: POST /images/{name}/push now supports a platform parameter (JSON encoded OCI Platform type) that allows selecting a specific platform-manifest from the multi-platform image. This is experimental and may change in future API versions. moby/moby#47679
  • POST /services/create and POST /services/{id}/update now support OomScoreAdj. moby/moby#47950
  • ContainerList api returns container annotations. moby/moby#47866
  • POST /containers/create and POST /services/create now take Options as part of HostConfig.Mounts.TmpfsOptions allowing to set options for tmpfs mounts. moby/moby#46809
  • The Healthcheck.StartInterval property is now correctly ignored when updating a Swarm service using API versions less than v1.44. moby/moby#47991
  • GET /events now supports image create event that is emitted when a new image is built regardless if it was tagged or not. moby/moby#47929
  • GET /info now includes a Containerd field containing information about the location of the containerd API socket and containerd namespaces used by the daemon to run containers and plugins. moby/moby#47239
  • Deprecate non-standard (config) fields in image inspect output. The Config field returned by this endpoint (used for docker image inspect) returned additional fields that are not part of the image's configuration and not part of the Docker Image Spec and the OCI Image Spec. These fields are never set (and always return the default value for the type), but are not omitted in the response when left empty. As these fields were not intended to be part of the image configuration response, they are deprecated, and will be removed in the future API versions.
  • Deprecate the daemon flag --api-cors-header and the corresponding daemon.json configuration option. These will be removed in the next major release. moby/moby#45313

The following deprecated fields are currently included in the API response, but are not part of the underlying image's Config: moby/moby#47941

  • Hostname
  • Domainname
  • AttachStdin
  • AttachStdout
  • AttachStderr
  • Tty
  • OpenStdin
  • StdinOnce
  • Image
  • NetworkDisabled (already omitted unless set)
  • MacAddress (already omitted unless set)
  • StopTimeout (already omitted unless set)

Go SDK changes

  • Client API callback for the following functions now require a context parameter. moby/moby#47536
    • client.RequestPrivilegeFunc
    • client.ImageSearchOptions.AcceptPermissionsFunc
    • image.ImportOptions.PrivilegeFunc
  • Remove deprecated aliases for Image types. moby/moby#47900
    • ImageImportOptions
    • ImageCreateOptions
    • ImagePullOptions
    • ImagePushOptions
    • ImageListOptions
    • ImageRemoveOptions
  • Introduce Ulimit type alias for github.com/docker/go-units.Ulimit. The Ulimit type as used in the API is defined in a Go module that will transition to a new location in future. A type alias is added to reduce the friction that comes with moving the type to a new location. The alias makes sure that existing code continues to work, but its definition may change in future. Users are recommended to use this alias instead of the units.Ulimit directly. moby/moby#48023

Move and rename types, changing their import paths and exported names. moby/moby#47936, moby/moby#47873, moby/moby#47887, moby/moby#47882, moby/moby#47921, moby/moby#48040

  • Move the following types to api/types/container:
    • BlkioStatEntry
    • BlkioStats
    • CPUStats
    • CPUUsage
    • ContainerExecInspect
    • ContainerPathStat
    • ContainerStats
    • ContainersPruneReport
    • CopyToContainerOptions
    • ExecConfig
    • ExecStartCheck
    • MemoryStats
    • NetworkStats
    • PidsStats
    • StatsJSON
    • Stats
    • StorageStats
    • ThrottlingData
  • Move the following types to api/types/image:
    • ImagesPruneReport
    • ImageImportSource
    • ImageLoadResponse
  • Move the ExecStartOptions type to api/types/backend.
  • Move the VolumesPruneReport type to api/types/volume.
  • Move the EventsOptions type to api/types/events.
  • Move the ImageSearchOptions type to api/types/registry.
  • Drop Network prefix and move the following types to api/types/network:
    • NetworkCreateResponse
    • NetworkConnect
    • NetworkDisconnect
    • NetworkInspectOptions
    • EndpointResource
    • NetworkListOptions
    • NetworkCreateOptions
    • NetworkCreateRequest
    • NetworksPruneReport
  • Move NetworkResource to api/types/network.

Packaging updates

27.0.0

There's no 27.0.0 release due to a mistake during the pre-release of 27.0.0-rc.1 on GitHub which resulted in the v27.0.0 tag being created. Unfortunately the tag was already picked up by the Go Module Mirror so it's not possible to cleanly change the v27.0.0. To workaround this, the 27.0.1 will be the first release of the 27.0.