Defacement: Internal Defacement
An adversary may deface systems internal to an organization in an attempt to intimidate or mislead users. This may take the form of modifications to internal websites, or directly to user systems with the replacement of the desktop wallpaper. Disturbing or offensive images may be used as a part of Internal Defacement in order to cause user discomfort, or to pressure compliance with accompanying messages. Since internally defacing systems exposes an adversary's presence, it often takes place after other intrusion goals have been accomplished.
Consider implementing IT disaster recovery plans that contain procedures for taking regular data backups that can be used to restore organizational data. Ensure backups are stored off system and is protected from common methods adversaries may use to gain access and destroy the backups to prevent recovery.
Monitor internal and websites for unplanned content changes. Monitor application logs for abnormal behavior that may indicate attempted or successful exploitation. Use deep packet inspection to look for artifacts of common exploit traffic, such as SQL injection. Web Application Firewalls may detect improper inputs attempting exploitation.