VerdantBamboo BRICKSTORM Sudo Privilege Escalation on Edge Appliance
Detects signs of the VerdantBamboo threat actor's BRICKSTORM/PLENET campaign, specifically targeting Linux-based edge appliances like pfSense and Synology NAS. The rule monitors for sudo abuse by specific service accounts (e.g., egnyteservice, www-data) attempting to leverage NOPASSWD sudo privileges for the 'tee' utility to write malicious content into sensitive system files (e.g., /usr/sbin/, /etc/cron.d/, /etc/sudoers). Additionally, it identifies unauthorized sudo enumeration commands that may indicate early-stage reconnaissance or persistence efforts.
Sigma
