Unable To Run Sudo On Terminal (Suspect Malware)

When I Run Any Sudo Commands I get:

sudo: /etc/sudoers is owned by uid 501, should be 0
sudo: no valid sudoers sources found, quitting
sudo: error initializing audit plugin sudoers_audit

This behavior starts at a failed mongodb installation and increased by the last 11.3.1 big sur update. Several Apps Crashing. I did a little research and some people recommends starts in safe mode and run:

chown root:wheel /etc/sudoers

But i forgotten (by now) the firmware password. So when i try to run any init shortcut prompts for the firmware password.
Please someone tell me what's happening.
Unable To Run Sudo On Terminal (Suspect Malware)
 
 
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