Some now-classic selections in the security freeware category are the Metasploit Framework open-source penetration testing tool, which is also commercialized by Rapid7; the NetCat mapping tool; the Nessus remote-security scanner; NetStumbler wireless network discovery tool; the nMap Security Scanner; and of course, Snort, the intrusion-detection and prevention system pioneered over at Sourcefire.
In addition, security vendors that want to get your attention are known to come up with lots of tools like free assessment scans of one sort of another, though the end goal of course is usually to sell you a subscription service.
Among the vendors that regularly announce free scans are Qualys for vulnerability assessment, eEye, Sophos, Symantec and McAfee. Microsoft has long offered its free Microsoft Baseline Security Analyzer, mainly for small to midsize businesses to check Windows for conformance with Microsoft security recommendations. However, it appears that Microsoft won't offer the tool for Windows 8.
Ellen Messmer is senior editor at Network World, an IDG publication and website, where she covers news and technology trends related to information security. Twitter: @MessmerE. Email: firstname.lastname@example.org.
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