Please reboot your system. Does that fix the issue?

This is happening with me too. When I run any program that requires root, the password prompt fails, and it closes.

This is an expected side-effect of the latest update of the package polkitd. You need to reboot the system after this upgrade.

It's written among the logs of apt full-upgrade (assuming you ran this command manually in a terminal), but the line is buried among other apt logs, so I guess most people won't see it...

┌──(kali㉿kali)-[~]
└─$ sudo apt update && sudo apt full-upgrade
[...]
Setting up libpolkit-gobject-1-0:amd64 (127+really127-0kali1)…
Setting up libpolkit-agent-1-0:amd64 (127+really127-0kali1)…
Setting up polkitd (127+really127-0kali1)…
Upgrading to this polkitd version requires a reboot, please reboot the system when convenient.
Created symlink '/etc/systemd/system/sockets.target.wants/polkit-agent-helper.socket' → '/usr/lib/systemd/system/polkit-agent-helper.socket'.
[...]

Please reboot your system. Does that fix the issue?

sudo apt update && sudo apt full-upgrade
not working

sudo

Wrongly cloned from # 0009622 and schould be closed.