Microsoft developers have warned that updates for Windows Server released as part of the December “Update Tuesday” may cause errors when creating new virtual machines on some Hyper-V hosts.
Let me remind you that we also reported that In December, Microsoft Fixed 49 Vulnerabilities and Two 0-Day Attacks, and also that Microsoft Developers Fixed a Critical Bug in Azure Cosmos DB.The issue is reported to only affect Windows Server/AzStack HCI hosts in SDN-enabled environments managed by System Center Virtual Machine Manager (SCVMM).
Microsoft experts stressed that the bug does not affect existing virtual machines and network adapters, and only applies to those created after installing the problematic update.
The company also believes that the problem only affected Windows Server 2019 and Windows Server 2022 with packages KB5021237 and KB5021249 installed.
| VMM Version | Hyper-V patched KB5021249/KB5021237 | SDN enabled | Affected |
| VMM 2019 | 2012 R2, 2016, 2019, HCI 21H2 | No | No |
| VMM 2019 | 2012 R2, 2016 | Yes | No |
| VMM 2019 | 2019, HCI 21H2 | Yes | Yes |
| VMM 2022 | 2016, 2019, 2022, HCI 22H2 | No | No |
| VMM 2022 | 2016 | Yes | No |
| VMM 2022 | 2019, 2022, HCI 22H2 | Yes | Yes |
Microsoft developers assure that they are already working on fixing the bug, but in the meantime, administrators are invited to use the workaround to solve the problem, detailed in the support team.
Also the media wrote, 0-Day Bug Was Found in Microsoft Exchange, and LockBit Ransomware Operators Are Exploiting It.
