BlackSuit Ransomware: VPN Brute-Force Attack Chain, TTPs, and IOCs from a 9-Day Intrusion

BlackSuit ransomware operators exploited password-only VPN access to infiltrate, persist, escalate, and encrypt an enterprise over nine days using living-off-the-land tactics, credential harvesting, and systematic defense evasion—highlighting the critical need for MFA, robust endpoint controls, and vigilant credential monitoring.