**I think i found the reason for my problem:
Subject:** Regression: PermitEmptyPasswords = true breaks SSH login in LXC (pam_setcred failure)
Description: After updating to NixOS 25.11/26.05 on Proxmox 9 (Kernel 7.0), SSH login fails with fatal: PAM: pam_setcred(): Failure setting user credentials.
Root Cause: The default LXC profile (example) often includes services.openssh.settings.PermitEmptyPasswords = true;. In recent PAM/shadow versions, this causes a fatal error during session initialization if a user actually provides a password or if the environment is strictly hardened.
Fix: Set services.openssh.settings.PermitRootLogin = false; or ensure it’s not enabled by default in the lxc-container.nix profile.
Can anyone confirm this?