Ransomware Prevention Case Study - GTA Accounting Firm
How Group 4 Networks protected a Mississauga accounting firm from ransomware during tax season - zero data loss, zero downtime,. Call (416) 623-9677.
Six weeks before the engagement began, they had experienced a near-miss: a staff member's workstation had been infected with malware that their existing antivirus (an endpoint security product that had not been updated in 11 months) failed to detect. The IT incident was discovered only because a partner noticed unusual outbound network traffic. The malware was removed manually, but the experience prompted the partners to finally seek a managed IT provider with proper cybersecurity capabilities.
Six weeks after the security stack was deployed, at 11:47pm on a Tuesday during the firm's tax season peak, a ransomware payload was delivered to a partner's workstation via a phishing email attachment that bypassed email scanning (a zero-day variant). SentinelOne detected the behavioral pattern of the encryption process starting, automatically isolated the endpoint from the network within 47 seconds, and sent an alert to the G4NS SOC.
The SOC analyst confirmed the isolation, blocked the attacker's command-and-control IP address at the Fortinet firewall, and notified the firm's managing partner via phone at 12:02am. The infected workstation was reimaged from clean backup and returned to service by 8:15am - before the partners arrived for the day. The attack affected one endpoint only, and zero client data was accessed or exfiltrated.
Deployed Veeam with immutable backup copies in Microsoft Azure Canada, separate from the production environment. Immutable backups cannot be modified, deleted, or encrypted by ransomware - even if the attacker gains full administrative access to the production environment. Tested recovery procedures, confirming all 400+ client files could be restored within 4 hours.
Deployed SentinelOne Singularity EDR on all 22 workstations and 4 servers. Connected all endpoints to G4NS's 24/7 SOC for real-time threat monitoring. Configured SentinelOne's autonomous response capability - when a threat is detected, the endpoint is automatically isolated from the network within seconds, containing the threat without requiring human intervention.
Enrolled the firm in G4NS's managed SOC service, providing round-the-clock monitoring of all endpoints, network traffic, and email. SOC analysts are notified of any suspicious activity within minutes and can take immediate action - isolating endpoints, blocking IPs, and escalating to the on-call response team - without waiting for the client to contact support.