for network admins to scan their own networks to proactively find any vulnerabilities before the bad guys find them.
Network scanners can tell you where your network is vulnerable to attack...
Defined
 (Vulnerability Scanner)
Scanners 101
Tested Products  (Opening ad?)
Windows-based Scanners
Online Port Scanner  (AuditMyPC.com)
Free Vulnerability Scanners
Free Port Scanners
Penetration Testing Whitepaper  (SANS Reading Room)
Reviews  (Not official)
Scanners 101
Tested Products  (Opening ad?)
Windows-based Scanners
Online Port Scanner  (AuditMyPC.com)
Free Vulnerability Scanners
Free Port Scanners
Penetration Testing Whitepaper  (SANS Reading Room)
Reviews  (Not official)
Vulnerability Scanners
Nessus   (TOP RATED)
License: Free to download and subscriptions for vulnerability updates from Tenable are available for two typesof users- Home users and Professional Users.
Home Page
Free Download
Installation & Usage
Review  (About.com)
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Nmap   (Port Scanner)
License InfoHome Page
Free Download
Review  (Answers.com)
Review  (About.com)
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Angry IP Scanner   (IP Address & Port Scanner)
License Info  (See also GPLv2)Home Page
Free Download  (Vendor)
Free Download  (Download.com)
Documentation
Feedback
FAQ
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NetCat
AboutHome Page  (GNU, 2004)
Free Download   (Unix/Linux)
Free Download  (Windows)
Cheat Sheet
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SuperScan 4
License: This tool may be downloaded for personal and/or non-commercial use.About
Home Page  (Foundstone Inc, 2003)
Free Download  (Vendor)
Free Download  (SnapFiles)
Review  (APCMag.com)
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Penetration Testing
SAINT
Home PageDownloads  (Data sheet, free trial, etc)
Commercial Products
SAINTexploit  (Pentest tool)
Review
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Metasploit  (Open source project that gives users a framework to create software for penetration testing)
License Info  (Opening ad?)Home Page  (Caution: May get blocked by some proxy servers as hacker site)
Framework
Free Download
Metasploit Blog
Review
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Security Analyzers
MBSA   (Microsoft Security Base Analyzer)
Home PageFree Download
Review  (About.com)
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NetChk Protect/Limited   (Patch Management)
Home PageFree Download
Commercial Download  (Includes trial version)
Review
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Tripwire   (Config Management)
Home PageProduct Info
Free Download  (Open source version)
Details
Review
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Web Scanners
Web App Scanners Explained  (Opening ad?)Top 10?  (Caution: Sectools.org - may get blocked by some proxy servers as hacker site)
Acunetix
Home PageProducts
Free Download  (Vendor)
Free Download  (Net-security.org)
Review
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NStalker
Home PageFree Download
Commercial Version
License Info & FAQ
Review
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WebScarab
Detailed InfoFree Download
Review  (Not official)
More Info