Announcing the Open-Source Release of ML Video Codec (MLVC)
Video codecs compress video for transmission or storage, reducing bandwidth and storage requirements. MLVC is a modern machine-learning-based codec that uses substantially less bandwidth than conventional codecs, improving streaming and video-call quality—especially on constrained or unreliable networks—while lowering delivery and storage costs. MLVC is the product iteration of DCVC (Deep Contextual Video Compression) family of NVC (Neural Video Codec), open sourced by Microsoft Research since 2021, with improved compression efficiency, real-time performance on commodity Neural Processing Units (NPUs), and cross-platform support. We recently published this work in the paper MLVC: Multi-platform Learned Video Codec for Real-World Deployment. We are releasing the source code because we believe the next generation of video coding will be built openly, and we want the broader community — researchers, video codec engineers, platform vendors, product teams, as well as general developer community — to build it with us. Why MLVC Traditional video codecs (e.g., H.264/AVC, H.265/HEVC) have served the industry for a long time, but each generation requires enormous engineering effort for incremental gains and needs dedicated hardware which takes years to become commonly available. MLVC replaces conventional primitives — motion estimation, transforms, entropy modeling — with end-to-end learned neural compression, trained directly against rate-distortion objectives, and run on general-purpose NPU devices. The table below compares MLVC to popular video codecs, showing its lower bitrate and resulting savings in bandwidth and storage. Resolution vs H.264 vs H.265 360p 87.8% 75.5% 540p 82.7% 65.4% For example, for 360p video at 30 fps, where H.264 requires 1 Mbps, MLVC requires roughly 122 kbps for equivalent quality — about one-eight the bitrate under real-time conditions. The inference compute was kept approximately equal for the 360p and 540p resolutions. These results are based on a P.910 subjective test and are based on the Video Conferencing Dataset (VCD) dataset that we developed and also recently released as an open-source project. The following video demo illustrates the extent of quality enhancement achieved by MLVC relative to H.265/HEVC at the same bitrate of 200kbps (please watch by opening in a new window for better demonstration) \ Beyond video compression efficiency, MLVC also offers: NPU-first design. MLVC is built to run almost entirely on the AI accelerators already shipping in modern devices — Apple Neural Engine, Qualcomm and Intel NPUs — at no more than 50% NPU utilization, leaving NPU headroom for the rest of the system. Real-time execution at the targeted operating points. Demonstrated 540p at 30 fps on Apple, Intel, and Qualcomm hardware. A scaling-law trajectory. Empirically, MLVC's coding efficiency improves with increased model capacity and additional training compute. Content-adaptive behavior out of the box, without hand-tuned Rate Distortion Optimization heuristics. Already running in Microsoft Teams MLVC is more than just a research concept for Microsoft. We are currently rolling it out in Microsoft Teams, where it is being validated on real peer-to-peer video calls with active telemetry and A/B testing. The integration runs alongside fallback to conventional video codecs for hardware or reliability constraints — the kind of mixed-environment deployment that real products need. The scaling and reliability insights from this rollout are shaping the codec and its roadmap. We welcome your contributions We can not cover every use case, every device class, or every content domain by ourselves. That is why we are open sourcing MLVC. If you work on: Streaming, Video On Demand (VOD), or live broadcast Real-time communication and conferencing Cloud gaming or remote rendering Surveillance, drones, or robotics Mobile capture, Augmented Reality (AR) / Virtual Reality (VR), or volumetric video Codec hardware, NPUs, or inference runtimes We would love your help. Contributions of all kinds are welcome, including model improvements, training recipes, new platform ports and conversion targets, runtime backends, domain-specific fine-tunes, evaluation tooling, bug reports, and feedback on what is missing for your scenario. We particularly welcome platform ports that expand NPU coverage and efficiency improvements that push the rate-distortion frontier. What's in the release The MLVC repository is available at https://github.com/microsoft/mlvc and shared under the MIT License. It includes: MLVC model source code of the full network architecture. Trained model weights ready to run. Training scripts used to produce shipping models. Training data collection documentation to help reproduce and improve MLVC. Platform conversion scripts to target different NPUs and runtimes. Issues and pull requests will be open from day one. A follow-up release will add a C++ codec library, simplifying integration into real-world applications. Where we're heading Our long-term goal with MLVC is to create an open, learned video codec that meets or exceeds the coding efficiency of the best conventional codecs across the full range of video content, runs efficiently on the AI hardware already shipping in client and cloud devices, scales with compute the way modern ML systems do, and evolves in the open at the pace of the ML community rather than the pace of standardization cycles. In the near term that means stabilizing 540p real-time performance, expanding hardware coverage, and improving loss resilience. In the medium term: higher resolution, e.g., 1080p, and broader streaming scenarios. In the long term: an open video codec ecosystem that meaningfully replaces legacy stacks where it makes sense to. We can't create the future of MLVC alone. We're glad you're here, and we are looking forward to building the next-generation video codec with you. Who are we MLVC is brought to you by the following awesome folks working on the project at Microsoft: Ross Cutler, Ando Saabas, Tanel Pärnamaa, Ardi Loot, Haiyan Xie, Lauri Ehrenpreis, Andrei Znobishchev, Martin Lumiste, Evgenii Indenbom, Yan Lu, Bin Li, Jiahao Li, Naba Kumar, Babak Naderi, Juhee Cho, Badal Yadav, Jinxin Zhou, Tianyu Ding, Patrick Gregory. — The MLVC Team, MicrosoftIncreased security and resiliency of Canonical workloads on Azure - now in preview
Microsoft and Canonical have partnered to make it easier for you to stay current with Linux operating system (OS) updates and increase the security and resiliency of Canonical workloads on Azure. Azure is the first cloud provider to collaborate with Canonical to integrate its snapshot service. Azure Guest Patching Service (AzGPS) and Azure Kubernetes Service (AKS) will leverage the new capability to apply the same update consistently on your fleet across regions via safe deployment principles (SDP).Run OpenClaw Agents on Azure Linux VMs (with Secure Defaults)
Many teams want an enterprise-ready personal AI assistant, but they need it on infrastructure they control, with security boundaries they can explain to IT. That is exactly where OpenClaw fits on Azure. OpenClaw is a self-hosted, always-on personal agent runtime you run in your enterprise environment and Azure infrastructure. Instead of relying only on a hosted chat app from a third-party provider, you can deploy, operate, and experiment with an agent on an Azure Linux VM you control — using your existing GitHub Copilot licenses, Azure OpenAI deployments, or API plans from OpenAI, Anthropic Claude, Google Gemini, and other model providers you already subscribe to. Once deployed on Azure, you can interact with an OpenClaw agent through familiar channels like Microsoft Teams, Slack, Telegram, WhatsApp, and many more! For Azure users, this gives you a practical middle ground: modern personal-agent workflows on familiar Azure infrastructure. What is OpenClaw, and how is it different from ChatGPT/Claude/chat apps? OpenClaw is a self-hosted personal agent runtime that can be hosted on Azure compute infrastructure. How it differs: ChatGPT/Claude apps are primarily hosted chat experiences tied to one provider's models OpenClaw is an always-on runtime you operate yourself, backed by your choice of model provider — GitHub Copilot, Azure OpenAI, OpenAI, Anthropic Claude, Google Gemini, and others OpenClaw lets you keep the runtime boundary in your own Azure VM environment within your Azure enterprise subscription In practice, OpenClaw is useful when you want a persistent assistant for operational and workflow tasks, with your own infrastructure as the control point. You bring whatever model provider and API plan you already have — OpenClaw connects to it. Why Azure Linux VMs? Azure Linux VMs are a strong fit because they provide: A suitable host machine for the OpenClaw agent to run on Enterprise-friendly infrastructure and identity workflows Repeatable provisioning via the Azure CLI Network hardening with NSG rules Managed SSH access through Azure Bastion instead of public SSH exposure How to Set Up OpenClaw on an Azure Linux VM This guide sets up an Azure Linux VM, applies NSG (Network Security Group) hardening, configures Azure Bastion for managed SSH access, and installs an always-on OpenClaw agent within the VM that you can interact with through various messaging channels. What you'll do Create Azure networking (VNet, subnets, NSG) and compute resources with the Azure CLI Apply Network Security Group rules so VM SSH is allowed only from Azure Bastion Use Azure Bastion for SSH access (no public IP on the VM) Install OpenClaw on the Azure VM Verify OpenClaw installation and configuration on the VM What you need An Azure subscription with permission to create compute and network resources Azure CLI installed (install steps) An SSH key pair (the guide covers generating one if needed) ~20–30 minutes Configure deployment Step 1: Sign in to Azure CLI az login # Select a suitable Azure subscription during Azure login az extension add -n ssh # SSH extension is required for Azure Bastion SSH The ssh extension is required for Azure Bastion native SSH tunneling. Step 2: Register required resource providers (one-time) Register required Azure Resource Providers (one time registration): az provider register --namespace Microsoft.Compute az provider register --namespace Microsoft.Network Verify registration. Wait until both show Registered. az provider show --namespace Microsoft.Compute --query registrationState -o tsv az provider show --namespace Microsoft.Network --query registrationState -o tsv Step 3: Set deployment variables Set the deployment environment variables that will be needed throughout this guide. RG="rg-openclaw" LOCATION="westus2" VNET_NAME="vnet-openclaw" VNET_PREFIX="10.40.0.0/16" VM_SUBNET_NAME="snet-openclaw-vm" VM_SUBNET_PREFIX="10.40.2.0/24" BASTION_SUBNET_PREFIX="10.40.1.0/26" NSG_NAME="nsg-openclaw-vm" VM_NAME="vm-openclaw" ADMIN_USERNAME="openclaw" BASTION_NAME="bas-openclaw" BASTION_PIP_NAME="pip-openclaw-bastion" Adjust names and CIDR ranges to fit your environment. The Bastion subnet must be at least /26. Step 4: Select SSH key Use your existing public key if you have one: SSH_PUB_KEY="$(cat ~/.ssh/id_ed25519.pub)" If you don't have an SSH key yet, generate one: ssh-keygen -t ed25519 -a 100 -f ~/.ssh/id_ed25519 -C "you@example.com" SSH_PUB_KEY="$(cat ~/.ssh/id_ed25519.pub)" Step 5: Select VM size and OS disk size VM_SIZE="Standard_B2as_v2" OS_DISK_SIZE_GB=64 Choose a VM size and OS disk size available in your subscription and region: Start smaller for light usage and scale up later Use more vCPU/RAM/disk for heavier automation, more channels, or larger model/tool workloads If a VM size is unavailable in your region or subscription quota, pick the closest available SKU List VM sizes available in your target region: az vm list-skus --location "${LOCATION}" --resource-type virtualMachines -o table Check your current vCPU and disk usage/quota: az vm list-usage --location "${LOCATION}" -o table Deploy Azure resources Step 1: Create the resource group The Azure resource group will contain all of the Azure resources that the OpenClaw agent needs. az group create -n "${RG}" -l "${LOCATION}" Step 2: Create the network security group Create the NSG and add rules so only the Bastion subnet can SSH into the VM. az network nsg create \ -g "${RG}" -n "${NSG_NAME}" -l "${LOCATION}" # Allow SSH from the Bastion subnet only az network nsg rule create \ -g "${RG}" --nsg-name "${NSG_NAME}" \ -n AllowSshFromBastionSubnet --priority 100 \ --access Allow --direction Inbound --protocol Tcp \ --source-address-prefixes "${BASTION_SUBNET_PREFIX}" \ --destination-port-ranges 22 # Deny SSH from the public internet az network nsg rule create \ -g "${RG}" --nsg-name "${NSG_NAME}" \ -n DenyInternetSsh --priority 110 \ --access Deny --direction Inbound --protocol Tcp \ --source-address-prefixes Internet \ --destination-port-ranges 22 # Deny SSH from other VNet sources az network nsg rule create \ -g "${RG}" --nsg-name "${NSG_NAME}" \ -n DenyVnetSsh --priority 120 \ --access Deny --direction Inbound --protocol Tcp \ --source-address-prefixes VirtualNetwork \ --destination-port-ranges 22 The rules are evaluated by priority (lowest number first): Bastion traffic is allowed at 100, then all other SSH is blocked at 110 and 120. Step 3: Create the virtual network and subnets Create the VNet with the VM subnet (NSG attached), then add the Bastion subnet. az network vnet create \ -g "${RG}" -n "${VNET_NAME}" -l "${LOCATION}" \ --address-prefixes "${VNET_PREFIX}" \ --subnet-name "${VM_SUBNET_NAME}" \ --subnet-prefixes "${VM_SUBNET_PREFIX}" # Attach the NSG to the VM subnet az network vnet subnet update \ -g "${RG}" --vnet-name "${VNET_NAME}" \ -n "${VM_SUBNET_NAME}" --nsg "${NSG_NAME}" # AzureBastionSubnet — name is required by Azure az network vnet subnet create \ -g "${RG}" --vnet-name "${VNET_NAME}" \ -n AzureBastionSubnet \ --address-prefixes "${BASTION_SUBNET_PREFIX}" Step 4: Create the Virtual Machine Create the VM with no public IP. SSH access for OpenClaw configuration will be exclusively through Azure Bastion. az vm create \ -g "${RG}" -n "${VM_NAME}" -l "${LOCATION}" \ --image "Canonical:ubuntu-24_04-lts:server:latest" \ --size "${VM_SIZE}" \ --os-disk-size-gb "${OS_DISK_SIZE_GB}" \ --storage-sku StandardSSD_LRS \ --admin-username "${ADMIN_USERNAME}" \ --ssh-key-values "${SSH_PUB_KEY}" \ --vnet-name "${VNET_NAME}" \ --subnet "${VM_SUBNET_NAME}" \ --public-ip-address "" \ --nsg "" --public-ip-address "" prevents a public IP from being assigned. --nsg "" skips creating a per-NIC NSG (the subnet-level NSG created earlier handles security). Reproducibility: The command above uses latest for the Ubuntu image. To pin a specific version, list available versions and replace latest: az vm image list \ --publisher Canonical --offer ubuntu-24_04-lts \ --sku server --all -o table Step 5: Create Azure Bastion Azure Bastion provides secure-managed SSH access to the VM without exposing a public IP. Bastion Standard SKU with tunneling is required for CLI-based "az network bastion ssh" command. az network public-ip create \ -g "${RG}" -n "${BASTION_PIP_NAME}" -l "${LOCATION}" \ --sku Standard --allocation-method Static az network bastion create \ -g "${RG}" -n "${BASTION_NAME}" -l "${LOCATION}" \ --vnet-name "${VNET_NAME}" \ --public-ip-address "${BASTION_PIP_NAME}" \ --sku Standard --enable-tunneling true Bastion provisioning typically takes 5–10 minutes but can take up to 15–30 minutes in some regions. Step 6: Verify Deployments After all resources are deployed, your resource group should look like the following: Install OpenClaw Step 1: SSH into the VM through Azure Bastion VM_ID="$(az vm show -g "${RG}" -n "${VM_NAME}" --query id -o tsv)" az network bastion ssh \ --name "${BASTION_NAME}" \ --resource-group "${RG}" \ --target-resource-id "${VM_ID}" \ --auth-type ssh-key \ --username "${ADMIN_USERNAME}" \ --ssh-key ~/.ssh/id_ed25519 Step 2: Install OpenClaw (in the Bastion SSH shell) curl -fsSL https://openclaw.ai/install.sh | bash The installer installs Node LTS and dependencies if not already present, installs OpenClaw, and launches the OpenClaw onboarding wizard. For more information, see the open source OpenClaw install docs. OpenClaw Onboarding: Choosing an AI Model Provider During OpenClaw onboarding, you'll choose the AI model provider for the OpenClaw agent. This can be GitHub Copilot, Azure OpenAI, OpenAI, Anthropic Claude, Google Gemini, or another supported provider. See the open source OpenClaw install docs for details on choosing an AI model provider when going through the onboarding wizard. Most enterprise Azure teams already have GitHub Copilot licenses. If that is your case, we recommend choosing the GitHub Copilot provider in the OpenClaw onboarding wizard. See the open source OpenClaw docs on configuring GitHub Copilot as the AI model provider. OpenClaw Onboarding: Setting up Messaging Channels During OpenClaw onboarding, there will be an optional step where you can set up various messaging channels to interact with your OpenClaw agent. For first time users, we recommend setting up Telegram due to ease of setup. Other messaging channels such as Microsoft Teams, Slack, WhatsApp, and others can also be set up. To configure OpenClaw for messaging through chat channels, see the open source OpenClaw chat channels docs. Step 3: Verify OpenClaw Configuration To validate that everything was set up correctly, run the following commands within the same Bastion SSH session: openclaw status openclaw gateway status If there are any issues reported, you can run the onboarding wizard again with the steps above. Alternatively, you can run the following command: openclaw doctor Message OpenClaw Once you have configured the OpenClaw agent to be reachable via various messaging channels, you can verify that it is responsive by messaging it. Enhancing OpenClaw for Use Cases There you go! You now have a 24/7, always-on personal AI agent, living on its own Azure VM environment. For awesome OpenClaw use cases, check out the awesome-openclaw-usecases repository. To enhance your OpenClaw agent with additional AI skills so that it can autonomously perform multi-step operations on any domain, check out the awesome-openclaw-skills repository. You can also check out ClawHub and ClawSkills, two popular open source skills directories that can enhance your OpenClaw agent. Cleanup To delete all resources created by this guide: az group delete -n "${RG}" --yes --no-wait This removes the resource group and everything inside it (VM, VNet, NSG, Bastion, public IP). This also deletes the OpenClaw agent running within the VM. If you'd like to dive deeper about deploying OpenClaw on Azure, please check out the open source OpenClaw on Azure docs.Canonical Ubuntu 20.04 LTS Reaching End of Standard Support
We’re announcing the upcoming end of standard support for Ubuntu 20.04 LTS (Focal Fossa) on 31 May 2025, as we focus on delivering a more secure and optimized Linux experience. Originally released in April 2020, Ubuntu 20.04 LTS introduced key enhancements like improved UEFI Secure Boot and broader Kernel Livepatch coverage, strengthening security on Azure. You can continue using your existing virtual machines, but after this date, security, features, and maintenance updates will no longer be provided by Canonical, which may impact system security and reliability. Recommended action: It’s important to act before 31 May 2025 to ensure you’re on a supported operating system. Microsoft recommends either migrating to the next Ubuntu LTS release or upgrading to Ubuntu Pro to gain access to expanded security and maintenance from Canonical. Upgrading to Ubuntu 22.04 LTS or Ubuntu 24.04 LTS Transitioning to the latest operating system, such as Ubuntu 24.04 LTS, is important for performance, hardware enablement, new technology benefits, and is recommended for new instances. It may be a complex process for existing deployments and should be properly scoped and tested with your workloads. While there’s no direct upgrade path from Ubuntu 20.04 LTS to Ubuntu 24.04 LTS, you can directly upgrade to Ubuntu 22.04 LTS, and then to Ubuntu 24.04 LTS, or directly install Ubuntu 24.04 LTS. See the Ubuntu Server upgrade guide for more information. Ubuntu Pro – Expanded Security Maintenance to 2030 Ubuntu Pro includes security patching for all Ubuntu packages due to Expanded Security Maintenance (ESM) for Infrastructure and Applications and optional 24/7 phone and ticket support. Ubuntu Pro 20.04 LTS will remain fully supported until May 2030. New virtual machines can be deployed with Ubuntu Pro from the Azure Marketplace. You can also upgrade existing virtual machines to Ubuntu Pro by in-place upgrades via Azure CLI. More Information More information covering Ubuntu 20.04 LTS End of Standard Support can be found here. Refer to the documentation to learn more about handling Ubuntu 20.04 LTS on Azure. You can also check out Canonical’s blog post and watch the webinar here.Introducing kars - an Agent Reference Stack for Kubernetes
kars is an open-source, Kubernetes-native runtime for AI agents on Azure. It treats every agent as untrusted code - per-pod kernel isolation, zero credentials in the agent process, and an end-to-end encrypted inter-agent mesh - and governs agents on any framework with one set of Kubernetes policies via the Microsoft Agent Governance Toolkit. kars dev runs a governed agent on your laptop in minutes.What IT teams need to know about Linux Secure Boot certificates expiring in 2026
If your organization does not use UEFI Secure Boot on Linux systems, this transition does not affect your boot path. You can stop reading now. If you do use Secure Boot, here is what you need to know. The Microsoft Corporation UEFI CA (Certificate Authority) 2011 expires on June 27, 2026 (June 26 local time in some time zones). Expiration alone does not stop anything from booting and does not render a system insecure. Existing 2011-signed shims keep working on systems that still trust the 2011 CA. The real risk is narrower: once an operating system vendor ships a shim signed only by the Microsoft UEFI CA 2023, any system whose firmware does not already trust the 2023 CA will fail to boot. The work for you is to confirm, before that update reaches your systems, that your systems trust the 2023 CA. If you want the history of why a Microsoft certificate sits in the Linux Secure Boot path at all, skip to the end. Terms used in this post You may see three Microsoft Secure Boot certificate authorities discussed in 2026 guidance. This post focuses on the Microsoft UEFI CA 2011, which is the CA used for third-party UEFI boot applications such as the Linux shim. The other expiring Microsoft Secure Boot certificates are the Microsoft Corporation KEK CA 2011, which is used to authorize updates to Secure Boot databases, and the Microsoft Windows Production PCA 2011, which is used for Windows boot components. Windows systems have a separate update path for those certificates; this post covers only the Linux boot chain. The 2023 update also separates two uses that were both covered by the Microsoft UEFI CA 2011. The Microsoft UEFI CA 2023 is for third-party UEFI boot applications, including the Linux shim. The Microsoft Option ROM UEFI CA 2023 is for third-party option ROMs, such as firmware on some add-in cards. This post is about the Linux bootloader path, but physical systems that rely on signed option ROMs may need to check that path too. Microsoft began returning 2023-signed Linux shim binaries to operating system vendors in October 2025, and since then a submitted shim comes back signed by both the 2011 CA and the 2023 CA. Once the 2011 CA expires, Microsoft can only sign with the 2023 CA. In UEFI Secure Boot terminology, db is the allowed signature database, dbx is the forbidden or revoked signature database, and KEK contains keys that can authorize updates to db and dbx . SBAT is a shim ecosystem mechanism for revoking boot components by generation. SBAT is related to Secure Boot revocation, but it is separate from the CA expiration itself. For brevity, the rest of this post uses operating system vendor to include Linux distributions and other vendors that ship and support Linux boot components. Microsoft returns signed shims to that submitting operating system vendor. It does not push shim updates to end users or IT departments. Those reach systems through the normal operating system, package, image, or platform update channels. What is not happening Expiration is not revocation, and it does not cause an immediate boot failure. The 2011 CA expiring does not make existing 2011-signed shims stop booting on June 27, 2026. UEFI Secure Boot validates a signature against the trust database and revocation state, not against the certificate's validity period. The image-validation process in the UEFI specification bases the decision on whether the image's hash or signing certificate is present in the authorized database ( db ) and absent from the forbidden database ( dbx ). It does not check whether the certificate has expired. Firmware bugs are always possible, but expiration by itself should not invalidate an already-signed shim. There is also no current plan to revoke the Microsoft UEFI CA 2011. Expiration means Microsoft can no longer sign new binaries with that certificate. Revocation would mean telling systems not to trust binaries signed with it. Revocation is not the plan. For the same reason, do not remove the 2011 CA from a system's Secure Boot db . Removing it strips that trust path. Removal is not required for this transition, and existing boot components may still depend on the 2011 CA. No operating system vendor has to move to a 2023-signed shim on the expiration date. An operating system vendor may keep shipping a 2011-signed shim (if one is available), ship a 2023-only shim, or ship one carrying both signatures. That decision belongs to the operating system vendor. What can break The failure case is a mismatch between the shim signature and the firmware trust database. The moment to worry about is not the expiration date. It is when a system first receives a 2023-only shim. That leaves a remediation window: the time between the expiration date and the first 2023-only shim reaching a given system. How long it lasts depends on your operating system vendor's packaging decisions, any security fix that forces a new shim release, and how easily you can update firmware or VM Secure Boot state on the affected platforms. The transition comes down to one table: Firmware trust database 2011-only shim 2023-only shim Dual-signed shim 2011 CA only Boots, but depends on continued 2011 trust Does not boot Should boot 2023 CA only Does not boot Boots Should boot Both 2011 and 2023 CAs Boots Boots Boots The table is deliberately simple. Real systems also have dbx revocations, SBAT policy, firmware bugs, operating system vendor packaging choices, and platform-specific update paths. But this is the core compatibility problem. Dual-signed shims help bridge the transition, because the same shim can validate through either CA. However, they are not a guarantee. Some firmware mishandles multiple signatures and evaluates only one of them, revocation and vendor support still apply, and the operating system vendor decides whether to ship and support a dual-signed shim at all. This kind of failure happens early, before the operating system loads. Recovery means restoring a trusted boot path or following your operating system, hardware, or platform vendor's recovery guidance. It is not a package rollback inside a running system. Who should pay closest attention This transition matters most where the operating system, firmware, and update path may not move together. If you run a maintained operating system on maintained hardware or a maintained virtualization platform, the normal vendor update path may handle most of it. Closer attention is worthwhile where that path is missing, delayed, customized, or hard to validate. Older hardware is the first case. Some systems need a firmware update before they can trust the 2023 CA, and support can vary by model even within one hardware vendor's portfolio. Check each model you operate rather than assuming one answer covers the fleet. Long-lived virtual machines are the second. VM firmware is still firmware. A VM's Secure Boot state depends on when it was created, which platform firmware it uses, and which UEFI variables have changed since. Firmware is not just another package update, so a long-lived VM may never have received the relevant firmware or database updates unless the administrator or platform applied them. Your cloud or virtualization provider should be able to say how the 2023 CA is handled for new VMs, existing VMs, and imported or custom images. For Azure Trusted Launch and Confidential VMs specifically, Microsoft has published guidance on identifying and updating affected instances. Older operating system releases need more careful validation. Some lack current Secure Boot tooling, current fwupd daemon behavior, or a supported path for updating UEFI trust databases. A command that works on one release may not be supported on another. Custom fleets are their own category: systems built from custom images, frozen package mirrors, pinned bootloader versions, or local Secure Boot policy changes. The more an environment differs from the vendor's default update path, the more you need to verify the actual firmware trust database and installed shim directly. Smaller operating system vendors and long-tail distributions are worth checking too, especially if they submit shim updates infrequently or have not finished their 2023 signing transition. No single authoritative public list tells you which releases have completed this work. Who is responsible for what There is no single Linux Secure Boot owner who can make every system safe for the transition. The operating system vendor controls which shim and boot components it ships. It also controls whether its update process checks the firmware trust database before installing a 2023-only shim. The Linux community runs a community-driven shim-review process for shim submissions. That process is the primary review gate before an operating system vendor requests a Microsoft signature. It is not a support channel for individual systems or fleets. The hardware vendor, firmware vendor, or virtual machine platform controls which trust anchors are present by default and how firmware updates are delivered. In a physical machine, that may mean a BIOS or firmware update. In a VM, it may mean platform firmware defaults, guest-visible UEFI variables, or a provider-specific remediation process. Microsoft controls the Microsoft UEFI signing service and the Microsoft UEFI CAs. After shim-review approval, Microsoft verifies the submitter's relationship to the operating system vendor, runs some additional checks, signs submitted shims, and returns the signed artifacts to the submitting operating system vendor. Microsoft does not choose when each operating system vendor ships a new shim to its customers. Your organization controls the systems it administers. In practice, that means checking whether Secure Boot is enabled, checking which certificates are trusted, following guidance from the relevant operating system vendor, and following guidance from the hardware vendor or VM provider. This is why the right answer for any specific system depends on its operating system vendor, hardware vendor, and platform. This post explains the model. Only those vendors can tell you what is supported for your systems. What to check The exact commands vary by operating system vendor, package set, and platform. Treat the examples below as illustrations, not guaranteed instructions for every Linux system. IT departments should validate commands against vendor documentation before using them in production automation. At fleet scale, the useful starting point is an inventory rather than a one-time manual check. Useful fields include whether Secure Boot is enabled, which Microsoft UEFI CAs are present in the firmware trust database, which CA signed the installed shim, the operating system release, the hardware model or VM platform, the update channel, and whether the system comes from a custom image or vendor image. Set up representative canary systems before any broad rollout. A canary set should cover the differences that matter in your fleet: hardware model, VM platform, operating system release, image lineage, and update channel. The aim is to avoid discovering a firmware or shim mismatch for the first time during a broad production update, not to build a new certification program. First, check whether Secure Boot is enabled: sudo mokutil --sb-state If Secure Boot is disabled, this certificate transition does not affect that system's current boot path. Next, check which Microsoft UEFI CAs are in the firmware trust database: sudo mokutil --db Look for entries such as: Microsoft Corporation UEFI CA 2011 Microsoft UEFI CA 2023 If both are present, the system is prepared for a future 2023-signed shim. If only the 2011 CA is present, check guidance from the relevant operating system vendor and platform provider before accepting a 2023-only shim update. On physical systems, also check whether the platform relies on signed third-party option ROMs. Those may require the Microsoft Option ROM UEFI CA 2023 in addition to the Microsoft UEFI CA 2023 used for boot applications. This is another reason hardware guidance can vary by model. Administrators can also inspect the signature on the shim currently installed on a system. On Enterprise Linux and related distributions, pesign is often used: sudo dnf install pesign sudo pesign -S -i /boot/efi/EFI/<vendor-or-distribution>/shimx64.efi On Debian, Ubuntu, and related distributions, sbverify from sbsigntools is often used: sudo apt install sbsigntools sudo sbverify --list /boot/efi/EFI/<vendor-or-distribution>/shimx64.efi The path to shim may differ. Some systems use a different EFI path, a different architecture suffix, or a different bootloader arrangement. Vendor documentation is the right source for exact commands. How updates may be delivered Many operating system vendors use the Linux Vendor Firmware Service (LVFS) and fwupd for firmware-related updates, including some UEFI Secure Boot database updates. Not every vendor enables the same tooling, and not every platform supports the same update mechanism. Common examples include: sudo fwupdmgr update sudo fwupdmgr security sudo fwupdmgr get-devices Some systems may require a firmware update from the hardware vendor. Some may support a standalone UEFI database update. Some may not support a safe standalone update at all. Some hardware and firmware vendors block standalone database updates because earlier failures showed that the update could break systems. Updating the Secure Boot allowed signature database ( db ) also depends on authorization from keys in KEK . That is one reason these updates often require cooperation from the firmware, hardware, or VM platform vendor. Administrators should not assume that possession of a certificate file is enough to update a system safely. Do not force a Secure Boot database update just because a command exists. Follow the guidance for the specific hardware, VM platform, or operating system vendor. Forcing an update can force a physical reboot of a machine or destroy the system. After the first inventory pass, keep watching the operating system vendor's security advisories and bootloader package updates. Questions for your vendors The right questions depend on the system, but these are the kinds of answers IT departments should look for from operating system vendors, hardware vendors, and VM providers: Does this operating system release currently ship a 2011-signed, 2023-signed, or dual-signed shim? If the vendor plans to ship a 2023-only shim, will the update process check whether the system trusts the 2023 CA before installing it? How is the Microsoft UEFI CA 2023 delivered for this hardware model, VM platform, or image? Is a standalone Secure Boot database update supported, or must the update arrive through a firmware update? Does support vary by hardware model, firmware version, VM generation, image type, or operating system release? What should administrators monitor for shim, GRUB, SBAT, db , KEK , or dbx updates related to this transition? What is the recommended validation path before broad deployment? What is the supported recovery path if a system receives an incompatible shim or firmware update and fails to boot? What to do now If an IT department administers Linux systems that use Secure Boot, the useful work is straightforward: Use the checks above to inventory Secure Boot state, trusted CAs, and installed shim signatures across representative systems. Identify the parts of the fleet most likely to diverge from default vendor paths, including older hardware, long-lived VMs, older operating system releases, custom images, and pinned bootloader packages. Read operating system, hardware, and VM provider guidance before accepting 2023-only shim updates or applying firmware and Secure Boot database updates. Test representative canary systems before rolling out shim or firmware changes broadly. Monitor operating system vendor advisories for shim and bootloader updates related to the transition. Avoid forcing low-level firmware or UEFI variable updates unless vendor guidance says to do so. How Linux got here UEFI Secure Boot was introduced to let firmware verify boot components before executing them. The firmware contains a trust database. If a bootloader is signed by a trusted certificate and is not blocked by revocation policy, the firmware can execute it. In the PC ecosystem, Microsoft has long operated the signing infrastructure used by Windows and by many third-party UEFI boot components. Linux operating system vendors do not have Microsoft sign the Linux kernel directly. Instead, they use a small first-stage bootloader called shim. The Linux shim is signed by Microsoft so firmware will start it. The shim then validates the next boot component, usually GRUB or another vendor-controlled bootloader, using keys controlled by the operating system vendor, not Microsoft. That structure lets Linux operating system vendors participate in the UEFI Secure Boot ecosystem while keeping control over their own boot chains. The shim code is developed publicly, and shim signing uses the community-run shim-review process before the Microsoft signing step. That split is important. The Linux community reviews shim submissions, and Microsoft operates the signing service that applies a signature firmware will trust. The certificate rotation affects this first handoff. Firmware must trust the CA that signed shim. If a future shim is signed only by the 2023 CA, the firmware needs the 2023 CA in its trust database. A system that keeps booting with a 2011-signed shim is not automatically broken or insecure on the expiration date. A system that moves to a 2023-signed shim needs to trust the 2023 CA; plan for that transition.
