File and Directory Permissions Modification

Adversaries may modify file or directory permissions to evade defenses.

Deletes itself

Modifies Watchdog functionality

Malware like Mirai modifies the Watchdog to prevent it restarting an infected system.

Creates/modifies Cron job

Cron allows running tasks on a schedule, and is commonly used for malware persistence.

Modifies init.d

Adds/modifies system service, likely for persistence.