Most headlines focus on the final act of a ransomware attack: the moment files are encrypted and the ransom note appears. But for the attacker, that is the finish line. The real work happens much earlier during what can be called the “Pre-Flight” phase.
Before a single file is locked, attackers spend days—sometimes weeks—performing internal reconnaissance. They move laterally through your network, mapping out your “crown jewels,” testing credentials, and looking for the most sensitive data to exfiltrate. If you can catch them during this reconnaissance phase, you don’t just recover from ransomware; you prevent it.
The Blind Spot: The “East-West” Visibility Gap
Traditional perimeter security is great at watching the “North-South” traffic (data entering or leaving your network). However, ransomware thrives in the “East-West“ zone—the internal traffic moving between servers, workstations, and cloud segments.
Once an attacker gains a foothold on a single low-privilege device, they use it as a launchpad. Because many organizations have limited visibility into internal traffic, these “Pre-Flight” checks often go unnoticed:
- Internal Port Scanning: Searching for open vulnerabilities on neighboring servers.
- Credential Stuffing: Attempting to use stolen passwords to log into internal databases.
- Lateral Movement: Hopping from a dev environment into production or from the cloud into your on-premise core.
How NFO Catches the Reconnaissance Phase
NetFlow Optimizer (NFO) provides the high-fidelity telemetry required to spot these subtle internal movements in real-time. By streaming enriched flow data to your SIEM, NFO turns your existing network infrastructure into a massive sensor grid.
1. Visualizing East-West Traffic
NFO unifies telemetry from every internal switch, router, and cloud gateway. This gives your security team total visibility into internal traffic patterns that bypass the firewall. When a workstation that normally only talks to an email server suddenly starts “knocking” on fifty different database ports, NFO ensures your SIEM sees it immediately.
2. Spotting “Low and Slow” Lateral Movement
Sophisticated attackers don’t blast the network; they move slowly to avoid triggering basic threshold alerts. NFO provides un-sampled, granular flow data, allowing your analytics platform to detect the tiny, repetitive patterns characteristic of lateral movement and credential testing.
3. Identity-Enriched Alerts
Context is everything. NFO enriches every internal flow with User Identity. Instead of seeing an anonymous IP address moving through your network, your SOC sees that “Contractor_Account_03” is suddenly attempting to access the HR payroll server. This identity context allows for instant verification and containment.
Conclusion: Stopping the Clock on Ransomware
Ransomware is a race against time. The longer an attacker can perform their “Pre-Flight” checks undetected, the more damage they can do.
By leveraging NetFlow Optimizer, you gain the internal visibility needed to disrupt the attack chain. Detecting lateral movement in real-time means you can isolate the infected host and revoke compromised credentials before the first file is ever encrypted. Stop the “Pre-Flight” check, and you stop the ransomware.
Are you watching your East-West traffic?
Contact us today to learn how NFO provides the visibility needed to stop ransomware in its tracks, or Schedule a Demo to see our real-time lateral movement detection in action.