Cumulative update KB5033375, released as part of December's Patch Tuesday, causes problems with Wi-Fi on some Windows 11 devices.
Judging by the messages on RedditV in social networks and on support forums Microsoft, many users have already encountered this problem, mostly representatives of small and medium-sized businesses. In addition, several educational institutions have already issued warnings (1, 2), recommending to his students to remove the update KB5033375 (and optional preview update KB50532288if installed).
For example, in a report from the University of British Columbia it says: “The issue affects corporate wireless networks (ubcsecure, ubcprivate, eduroam) but does not affect home wireless/internet usage.”
Judging by the reports of victims, this problem actually affects corporate wireless networks with fast-transition and fast-roaming functions enabled, which are used to ensure “seamless” movement of devices between access points.
Home users who installed KB5033375 or KB50532288 have not yet complained of problems connecting to Wi-Fi. Additionally, the situation seems to only affect devices running Windows 11 (specifically versions 22H2 or 23H2). Windows 10 users do not appear to be affected by this error.
Since there has been no official announcement from Microsoft yet, it is currently unknown whether the wireless connection issues are specific to specific wireless adapter models or something else.
As a workaround, users can try switching from EAP-TLS to PEAP or disabling 802.11r on the affected SSID as the root of the problem appears to be the four-way handshake. You can also simply uninstall the December cumulative update KB5033375 for Windows 11 and the associated optional preview update KB50532288, if installed.