virustotal bot

What is VirusTotal?

VirusTotal is a security service that analyzes files and URLs for malicious content by checking them against multiple antivirus engines and website scanners. Operated by Chronicle Security (a subsidiary of Google), VirusTotal serves as a comprehensive threat intelligence platform that helps users identify potential security threats. The service was first created in 2004 by Hispasec Sistemas and was later acquired by Google in 2012.

Technically, VirusTotal operates as a specialized web crawler and scanning tool. When VirusTotal visits your website, it typically identifies itself with a user agent string that includes VirusTotal or related identifiers. The service works by examining web content for potential security threats, malware, phishing attempts, or other suspicious elements.

VirusTotal's primary function is to aggregate the scanning capabilities of dozens of security products and services, providing a "second opinion" on the safety of files and websites. The platform maintains a vast database of known threats and provides detailed reports on detected issues. You can learn more about VirusTotal's services at their official website.

Why is VirusTotal crawling my site?

VirusTotal may be crawling your website for several reasons. Most commonly, someone has submitted your website URL for analysis through VirusTotal's scanning service. This could be a security researcher, a concerned user, or even yourself if you've used the service to check your site's security status.

The frequency of VirusTotal's visits depends on how often your site is submitted for scanning. Unlike search engine crawlers that visit regularly to index content, VirusTotal typically only visits when specifically directed to analyze a URL. This means visits are generally sporadic rather than scheduled.

The crawling is typically triggered by manual submissions or automated security systems that use VirusTotal's API to check suspicious URLs. These scans are generally considered authorized use of the service, as VirusTotal provides a legitimate security function by helping identify potentially compromised websites.

What is the purpose of VirusTotal?

VirusTotal's primary purpose is to provide comprehensive security analysis of files and websites. The service supports internet safety by detecting malware, phishing attempts, and other security threats. When VirusTotal scans your website, it's checking for malicious code, suspicious behavior, or known security vulnerabilities.

The collected data is used to generate security reports that help users determine if a website is safe to visit. These reports include detailed information about any detected threats and the assessment from multiple security engines. This aggregated approach provides a more thorough security evaluation than a single antivirus solution.

For website owners, VirusTotal can provide value by identifying potential security issues that might otherwise go unnoticed. If your site has been compromised or is inadvertently hosting malicious content, a VirusTotal scan can help bring this to your attention so you can address the problem.

How do I block VirusTotal?

VirusTotal generally respects robots.txt directives, which means you can use this standard method to control its access to your site. To block VirusTotal completely, you can add the following to your robots.txt file:

User-agent: VirusTotal
Disallow: /

If you want to block VirusTotal from specific sections of your website while allowing it to scan others, you can use more targeted directives:

User-agent: VirusTotal
Disallow: /private/
Disallow: /members/
Allow: /

Before blocking VirusTotal, consider the potential consequences. Blocking this service might prevent legitimate security checks that could help identify if your site has been compromised. Security researchers and potential users might also view the inability to scan your site as suspicious.

If you're concerned about the impact of VirusTotal scans on your server performance, a better approach might be to implement rate limiting rather than blocking the service entirely. This allows security checks to continue while preventing excessive resource usage from repeated scans.

Remember that VirusTotal serves a beneficial security function for the internet community, and blocking it should be done only after careful consideration of the potential downsides.