ClamAV is an open-source antivirus engine for detecting trojans, viruses, malware & other malicious threats.
https://www.clamav.net/
<ol style="list-style-type: decimal"><li>ClamAV is designed to scan files quickly.</li>
<li>Real-time protection (Linux only). The ClamOnAcc client for the ClamD scanning daemon offers real-time scanning on modern versions of Linux. This includes an optional ability to block access to files until a file has been scanned (real-time prevention).</li>
<li>ClamAV detects millions of viruses, worms, Trojans and other malware, including Microsoft Office macro viruses, mobile malware and other threats.</li>
<li>Signed signature databases ensure that ClamAV will only execute trusted signature definitions.</li>
<li>ClamAV scans inside compressed archives, but also protects against archive bombs.</li>
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