Interpreting VirusTotal Outcomes: Why a Limited Number of Antivirus Detections Don’t Equal a Likely False Alarm

Decoding VirusTotal Results: Why a Few AV Detections Don’t Necessarily Equal a False Positive

Introduction

Navigating the world of antivirus detections can be tricky, particularly when using tools like VirusTotal (VT). Many users, including myself until recently, have often perceived detections from a handful of antivirus engines as likely false positives. However, this view can lead to misconceptions, which could compromise your cybersecurity efforts. Let’s delve deeper into how to interpret VT results effectively.

Understanding Detection Scores

The first step in analyzing your VT results is the detection count. It’s crucial to remember that antivirus descriptions can evolve. Before drawing conclusions, consider the following:

• Reanalysis: Regularly scanning files is beneficial. If VT has archived your file, it may have changed its detection status since the last analysis, reflecting evolving antivirus algorithms.
• malware Naming: Look for specific terms in the results. Labels such as “not-a-virus” from Kaspersky indicate that while the file may not be outright malicious, it could be used inappropriately. Not all antivirus tools use this classification, so keep that in mind.

Detailed Examination

Digging deeper into the file’s details can reveal a lot about its legitimacy:

• File Type Verification: Ensure that the file type aligns with its stated nature. Mismatched types can be a red flag.
• Submission History: Check the first submission date. If it predates the actual release of the Software in question, it’s a strong indication that the file is potentially outdated malware.
• Alternative Filenames: Investigate any alternative names associated with the file. If these names indicate unrelated content, you may be dealing with renamed malware. Common names like update.exe or test.pdf typically aren’t cause for concern, but unusual strings should be scrutinized.

Behavioral Analysis

Understanding the file’s behavior can highlight its intentions:

• File Actions: Examine what actions the file performs—such as dropping, deleting, or writing files. If it accesses parts of your system that seem excessive or unnecessary, it is worth investigating further.
• Registry Modifications: Genuine Software updates typically shouldn’t interfere with system protections like Windows Defender, so be wary of any such changes.
• Highlighted Calls: Specific function calls can also provide insights. For instance, if a file uses the GetTickCount function improperly, it might be attempting to recognize virtual environments