Windows 7: New, unusual targeted attack against MS Office in the wild

Symantec Corporation warns users about a new targeted attack against Office, potentially capable of exploiting an already patched vulnerability found in the most recent editions of the popular productivity suite published by Microsoft.

The trojan detected by the security enterprise (Trojan.Activehijack) comes as an archive attached to a malicious (likely spam) e-mail, and is crafted to exploit one of the vulnerabilities described in the MS11-073 Security Bulletin published on September 2011. The affected software suites include MS Office 2003 (SP3), Office 2007 (SP2) and Office 2010.

The already patched flaw is exploited in a way that is unusual among targeted attacks, Symantec explains: while previously identified attacks come as a single document file containing the exploit, this new one arrives as a pair of files – a Word document and a .dll library file.