Decoding VirusTotal Results: Beyond the ‘False Positive’ Myth

Understanding the intricacies of VirusTotal (VT) results can be a game changer in your cybersecurity toolkit. It’s crucial to move past the notion that a few antivirus detections indicate a file is likely harmless.

A Personal Note

It’s worth mentioning that I recently shifted my own perspective on this topic, so I completely empathize with anyone who may still hold this belief.

For a comprehensive overview of interpreting VirusTotal results, take a moment to watch the insightful video by MalwareAnalysisForHedgehogs: Watch Here.

Key Concepts to Consider

Detection

Reanalyze Regularly: malware detection is not static; it evolves over time. If a file hasn’t been scanned recently, it’s prudent to initiate a reanalysis. VT provides historical scan data, so be sure to check for prior results.
Evaluate malware Classification: Examine the names attributed to potential threats. Labels like “not-a-virus” may suggest that the file isn’t inherently harmful but could be misused. However, not all antivirus vendors employ this classification.

Detailed Examination

File Type Verification: Confirm that the file is what it claims to be. A discrepancy could indicate a deeper issue.
Submission Date: If the first submission date of the file predates the release of the Software you’re examining, it might be recycled malware.
Cross-Check File Names: If the detected names are irrelevant or entirely unrelated, it’s likely a case of renamed malware. However, generic names such as update.exe or test.pdf can often be dismissed.

Behavioral Analysis

File Activity Monitoring: Investigate what files are added, deleted, or written. Unexpected file paths can signal a problem.
Registry Actions: If the Software update disables critical security features like Windows Defender or Task Manager, it raises red flags.
VM Detection Techniques: Certain function calls, such as GetTickCount, can indicate attempts to detect virtual machines, which may be part of evasion tactics (for additional insights, refer to this FireEye article).