During an Advanced Continual Threat Hunt (ACTH) investigation that took place in early December 2023, Trustwave SpiderLabs discovered Ov3r_Stealer, an infostealer distributed using Facebook advertising and phishing emails. SpiderLabs’ “Facebook Advertising Spreads Novel Malware Variant,” is an in-depth dive into Ov3r_Stealer, exposing what the Threat Hunt team learned about the threat actors, their techniques, tactics, and procedures and how the malware functions.