In today’s evolving threat landscape, malware authors aren’t just creating new variants—they’re creating malware that’s built to evade. Zero-day threats and unknown malware strains exploit this gap in traditional defense tools by hiding in plain sight. These threats bypass static defenses because, by definition, there are no known signatures to match. For security teams and Managed Service Providers (MSPs), this is where behavior-based analysis becomes mission-critical.
Signature Scanning: A Limiting Legacy
Signature-based detection tools rely on known patterns—specific code fragments or hashes linked to previously observed malware. While effective for mass-known threats, they fall short against any malware that changes its signature or uses novel code. Modern attackers know this and design malware that morphs constantly or uses legitimate-looking code until it activates.
Take, for example, the SolarWinds attack in 2020. The malicious code inserted into Orion updates was digitally signed, passed static checks, and looked like business as usual. It wasn’t until researchers analyzed its behavior—the unauthorized command-and-control communication and privilege escalation—that the threat was uncovered. Static defenses alone missed it.
Case Study: Emotet’s Polymorphism
The Emotet malware family is another standout example. It constantly modified its payload to bypass signature detection tools, often within hours of being flagged. What made it identifiable wasn’t its code, which kept changing, but its behavior: establishing persistent footholds, using lateral movement tactics, and engaging in credential harvesting.
Behavior-based analysis, which observes how a file interacts with memory, the operating system, and external systems, exposes these consistent behaviors. No matter how much the binary changes, the malicious intent remains detectable—if you're watching the right signals.
Behavior Reveals the Undetectable
Behavior-based analysis doesn’t rely on what malware looks like, but rather what it does. It’s how defenders caught the early variants of Cobalt Strike being misused by attackers despite its legitimate use in red teaming. And it’s how advanced threats like FIN7’s tools, which often mimic legitimate admin utilities, get flagged when they begin executing malicious sequences.
Even unknown malware strains—those never seen before—can be identified by behavior-based tools when they deviate from typical application processes, modify critical system files, or initiate suspicious network connections.
The CodeHunter Solution
CodeHunter automates behavior-based malware analysis, combining patented static, dynamic, and AI-driven techniques to uncover threats that traditional scanners miss. It identifies zero-day and unknown malware in minutes by observing behavior patterns, persistence methods, and post-execution activity. Whether you're an MSP or an internal SOC team, CodeHunter enables you to respond quickly and confidently to threats that would otherwise slip through your defenses. Discover how CodeHunter can better protect your organization here.
