"For users of Office prior to 2010, the Enhanced Mitigation Experience Toolkit (EMET) can help," said Andrew Roths and Chengyun Chu, a manager and security engineer, respectively, with the Microsoft Security Response Center (MSRC). "Turning on EMET for the core Office applications will enable a number of security protections called 'security mitigations'," the pair wrote in a Thursday post to the company's blog.

EMET is a tool designed for advanced users, primarily enterprise IT pros, that manually enables ASLR (address space layout randomization) and DEP (data execution prevention) for specific applications. ASLR and DEP are two anti-exploit technologies included with Windows.

On Tuesday, Adobe confirmed that an unpatched bug in Flash Player by sending potential victims malicious Microsoft Excel documents.

Excel is the spreadsheet bundled with the Office suite.

According to Roths and Chu, Excel 2010, the version included with Office 2010, is not susceptible to the attacks now in circulation because that edition of the spreadsheet has DEP enabled. "The current attacks do not bypass DEP," they said.