By Jeff Mason
WASHINGTON (Reuters) – The White House on Sunday called on computer network operators to take further steps to assess whether their systems were targeted amid a hacking of Microsoft’s Corp Outlook e-mail program, saying a recent software package still left serious vulnerabilities.
“This is an active threat that is still evolving and we urge network operators to take it very seriously,” a White House spokesman said, adding that senior US security officials were working to decide what to do next after the breach.
CNN reported separately on Sunday that the Biden administration had formed a working group to deal with the hack. In a statement, a White House spokesman said the administration was making a “full response to the government”
While Microsoft released a patch last week to reveal flaws in its e-mail software, the drug still leaves a so-called backdoor open, which can allow access to compromised servers and immortalize additional attacks by others.
“We cannot stress enough that fixing and mitigation are not removals if the servers are already compromised, and it is essential that any organization with a vulnerable server take action to determine if they have already been targeted,” the White House official said.
A source has already told Reuters that more than 20,000 US organizations have been compromised by the hacking that Microsoft blames on China, although Beijing denies any role.
Reverse remote access channels can affect credit unions, city governments and small businesses and have left US officials struggling to reach victims, and the FBI on Sunday urged them to contact law enforcement.
Those affected appear to be hosting web versions of the Microsoft Outlook e-mail program on their own machines instead of cloud vendors, likely saving many large companies and federal government agencies, according to investigation records.
A Microsoft spokesman said Sunday that he was working with the government and others to help target customers, and the company urged affected customers to implement software updates as soon as possible.
Neither the company nor the White House have specified the scale of the hacking. Microsoft initially said it was limited, but the White House last week expressed concern about the potential for “large numbers of victims.”
So far, only a small percentage of infected networks have been compromised through the back door, the source told Reuters earlier, but more attacks are expected.
(Report by Jeff Mason; Additional Report by Susan Heavy and Sarah N. Lynch in Washington and David French in New York; Edited by Lisa Schumacher)