[Bug]: As of the May out-of-band Windows patch NAT networks no longer work

[cschuber]

Version

7.2.8

Host OS Type

Windows

Host OS name + version

FreeBSD 15 and Fedora 44

Host Architecture

x86

Guest OS Type

all

Guest Architecture

x86

Guest OS name + version

No response

Component

Network

What happened?

As of Microsoft patch KB5089466 NAT networks no longer work. Bridge and host-only still work. From FreeBSD 15 and Fedora 44 guests I am able to ping and arping the VBox provided DHCP server on the NAT network but I am unable to ping or arping the gateway. The NAT network remains unusable.

VirtualBox 7.2.8 has been reinstalled and I did also try the 7.2.9 stable snapshot. The problem persists. The host is Windows 11 25H2 with KB5089466. The guests are FreeBSD 15 and Fedora 44. Both have the same issue. The NAT network was working until yesterday when KB5089466. NAT no longer works after KB5089466 was installed by Windows update.

How can we reproduce this?

Install VBox on Windows 11 25H2. Add some VMs. Update the host with KB5089466. NAT will stop working.

Did you upload all of your necessary log files, screenshots, etc.?

• Yes, I've uploaded all pertinent files to this issue.