5 Most Common Security Attack Methods in 2024: Mandiant’s M-Trends Report

Mandiant's M-Trends 2025 summary reports an uptick in infostealer activity and ongoing widespread exploitation of known vulnerabilities and stolen credentials across finance, business services, high tech, government, and healthcare; primary initial access methods in 2024 included exploits, stolen credentials, phishing, and web compromise, while backdoors, ransomware, and credential-stealing malware were commonly observed—APT and state-affiliated actors plus financially motivated cybercriminals drove much of the data theft, prompting recommendations for patching, endpoint script blocking, content filtering, and securing internet-exposed systems.