MICROSOFT has a habit of hiding the real severity of its security flaws (and numbers). Despite or because of this Microsoft loves to pretend that it is leading among those who patch their software, but IBM's report suggests otherwise. Microsoft is positioned worst among everyone after some amendments were made:

IBM has overhauled its list of worst security patchers among software vendors, putting Microsoft at the top of its list and shifting Sun from No. 1 to No. 5.

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The corrected ranking for the companies with the most unpatched disclosed vulnerabilities by company name and percent unpatched is: Microsoft, 23%; Mozilla, 17%; Apple, 12%; IBM, 9%; Sun, 8%; Oracle, 6%; Cisco, 6%; Novell, 5%; HP, 4%; Linux, 3%; Adobe, 3%; Google, 0%.