Microsoft is currently working to patch a security bug that leaves users of Internet Explorer 6 to 11, which accounts for 55 percent of the Internet browser search market right now, exposed to targeted attacks from cybercriminals.
"It's a campaign of targeted attacks seemingly against U.S.-based firms, currently tied to defense and financial sectors," said Vitor De Souza, FireEye spokesman, in a statement to Reuters. "It's unclear what the motives of this attack group are, at this point. It appears to be broad-spectrum intel gathering."
FireEye didn't disclose which cybercriminals groups are reportedly behind "Operation Clandestine Fox," and didn't say which companies might have been compromised. As expected, following the April 8 end of support deadline, Windows XP users won't receive an update for the IE bug. It's believed 15 to 25 percent of PCs currently use XP, so cybercriminals have a large pool of exposed PCs they can target.