Categories October Surprise 2016 Open Source Nessus Alternatives: Top 13 Vulnerability Scanners Post author By Mike Nova Post date November 28, 2025 The best open source alternative to Nessus is SiteOne Crawler. If that doesn’t suit you, our users have ranked more than 25 alternatives to Nessus and 13 is open source so hopefully you can find a suitable replacement. ← YouTube For Families Help – Google Help → 1:18 1:18 Now playing, Trump calls release of Russia report a ‘disgrace,’ likens to Nazi Germany