Symantec researchers have uncovered a Trojan that targets a previously patched Microsoft Office security flaw.

"The exploit, which is being used in targeted attacks, arrives as an email that contains a Microsoft Word file and a separate DLL file, a rare combination considering DLL files are not typically sent over email," writes SC Magazine's Dan Kaplan.

"The trojan, dubbed 'Activehijack' by Symantec, takes advantage of a vulnerability rated 'important' that was patched by Microsoft in September with bulletin MS11-073," Kaplan writes.

Go to "Trojan appears that leverages patched Microsoft Office flaw" to read the details.

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