White House cites 'active threat,' urges action despite Microsoft patch

FILE PHOTO: A Microsoft logo is seen in Los Angeles, California U.S. November 7, 2017. REUTERS/Lucy Nicholson

WASHINGTON (Reuters) - The White House on Sunday urged computer network operators to take further steps to gauge whether their systems were targeted amid a hack of Microsoft Corp's Outlook email program, saying a recent software patch still left serious vulnerabilities.

"This is an active threat still developing and we urge network operators to take it very seriously," a White House official said, adding that top U.S. security officials were working to decide what next steps to take following the breach.