Out-of-band update: Microsoft fixes Message Queuing issues

Early this week, it became known that the security updates for Windows in December have unwanted side effects: message queuing (MSMQ), which is used for application communication, is disrupted by them in Windows 10 and Windows Servers up to 2019, which can lead to software failures. Microsoft is now intervening with out-of-band emergency updates.

Microsoft updated the entry in the Windows Release Health notes on Friday night with this solution. The update with the Knowledgebase entry KB5074976 (Windows 10), KB5074975 (Windows Server 2019) respectively KB5074974 (Windows Server 2016) is now available and brings the Windows 10 build numbers to 19044.6693 and 19045.6693. It is a cumulative update, also including the other changes from Microsoft's December Patchday.

Emergency updates only partially available

IT administrators can only obtain the update via the Windows Update Catalog by searching for the KB number. Microsoft also links to the Windows Update Catalog accordingly in the KB entries, but at the time of reporting, the updates for servers are not yet available for download, contrary to the announcement.

Microsoft has since significantly expanded the list of affected operating systems. While it was initially stated that Windows 10 22H2, Windows Server 2016 and 2019 showed MSMQ problems after the update, Microsoft now lists Windows 10 22H2, 21H2, 1809 and 1607, as well as the server versions 2019, 2016, 2012 R2, and 2012 as being susceptible to it.

The issues with the December update became known on Monday this week. The disruptions stem from the changes made to the MSMQ security model and NTFS access rights for the “C:\Windows\System32\MSMQ\storage” folder. MSMQ users now need write access to this folder, which is usually restricted to administrators. As a result, attempts to send messages using MSMQ APIs can fail with resource errors.

(dmk)