To prevent the vsock-based sshd from auto-spawning, see 
https://www.freedesktop.org/software/systemd/man/devel/systemd-ssh-generator.html

In short: `systemd.ssh_auto=no` is the kernel-command-line setting which 
persists after reboots.

~Benjamin

________________________________________
From: Jacob Bachmeyer <[email protected]>
Sent: Sunday, December 28, 2025 10:11 PM
To: [email protected] <[email protected]>; Greg 
Dahlman <[email protected]>
Subject: Re: [oss-security] Systemd vsock sshd


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On 12/27/25 21:46, Greg Dahlman wrote:
> [...]
>
>   **Systemd v256 change** - When the *openssh-server* package is
>   installed on a VM with vsock support, systemd now automatically
>   starts an *sshd* instance that listens on the **af_vsock** socket in
>   the **global network namespace** without any manual configuration.

Obvious question:  what manual configuration is required to kill that
listener?


-- Jacob



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