Not sure if you've noticed this edit:
It wasn't hacked. The file was a temporary script I created during emergency maintenance in 2021-2022, when cPanel was inaccessible and Plesk had not yet been deployed.
It was recently flagged by the system. Since the file was created a long time ago, I didn't immediately recall it.
If a reset is still required, there's no need to back up the files, as I have copies of the important files locally.