Computer systems in the White House have been under a sustained cyberattack for two weeks, and Russian hackers are being blamed for the attack.
US government officials have spoken anonymously about the attack, but have made it clear that, to date, no systems have been damaged nor any classified networks breached.
Speaking to the Washington Post, one source said:
In the course of assessing recent threats, we identified activity of concern on the unclassified Executive Office of the President network," said one White House official. "We took immediate measures to evaluate and mitigate the activity… Unfortunately, some of that resulted in the disruption of regular services to users. But people were on it and are dealing with it.
Talking to the Huffington Post, a person familiar with the matter said the current attack was much more powerful than the typical attacks which target the White House systems which "indicates significant strength".
The Washington Post attributes the attack to Russian hackers quoting sources who said "the nature of the target is consistent with a state-sponsored campaign".
On Tuesday, it was revealed by security firm FireEye that hackers affiliated with the Russian government have been behind a wide range of cyberattacks against targets in the US and Europe, as well as targeting organisations such as Nato.
The current attack has seen some White House staff forced to change their passwords and knocked out VPN (virtual private network – encrypted computer connections) and intranet access for a time, however officials say that email only suffered very minor delays.
The US government says it is the constantly under attack from hackers, but typical cyberattacks make little to no impact on the robust defences which are now in place.
The Huffington Post also published an internal White House memo emailed to staff about the attack:
As you are aware, technical issues have resulted in limited access to some EOP network services. We understand that many users depend on these capabilities, and we apologise for what we know is an inconvenience. Some of these issues have been resolved, and we have also been working with EOP component heads and NSC Senior Directors to put in place a number of interim measures to help employees work on high priority requests as we continue to resolve the remaining issues as soon as possible.
Some of these issues have been resolved, and we have also been working with EOP component heads and NSC Senior Directors to put in place a number of interim measures to help employees work on high priority requests as we continue to resolve the remaining issues as soon as possible. With those measures in place, we want to share additional information so you are aware of what is causing these technical issues.
The Executive Office of the President receives alerts concerning numerous possible cyber threats on a daily basis. We take each of these threats very seriously, and we regularly evaluate our security measures and take action to defend our networks and mitigate those threats.
In the course of assessing recent threats, we identified activity of concern on the unclassified EOP network. Any such activity is something we take very seriously. In this case, we took immediate measures to evaluate and mitigate the activity. Our actions are ongoing, and some have resulted in temporary outages and loss of connectivity for our users.
Our computers and systems have not been damaged, though some elements of the unclassified network have been affected. The temporary outages and loss of connectivity that users have been experiencing is solely the result of measures we have taken to defend our networks.
We appreciate your patience as we continue to work with you to provide you the capabilities you need as soon as possible. If you are contacted on this issue by anyone outside of EOP, to include members of the press, please refer them to the White House press office.