These reports were confirmed by the FBI, who said that they had to shut down their intranet because of a disruption in their unclassified network.
However, they did dispute rumors stating that this attack had left FBI crippled and unable to contact their counterparts and other law enforcement agencies across the world via email.
On the contrary, they had stated that the unclassified, external network of FBI was shut down mainly as a precautionary measure, and nothing else.
This is why the FBI had managed to restore email traffic via the external and unclassified network within 48 hours of the identification of the issuer and mitigating risks.
Moreover, the FBI basically sends their important emails using their more secure and internal network or with the help of BlackBerry and are not that dependent on this unclassified network for communication.
Shut down for technical reasons This unclassified and external network is used by only some FBI personnel to send messages through the web-based email system.
It was this system that was shutdown in the week, and rendered useless and unavailable to many users.
The FBI stated that there was nothing to worry about this attack as they can still email anyone with their private internet access.
They also have a secure email system that is effective in connecting all their offices across the country and overseas.
Although the FBI did not actually provide any information about the attack, by the looks of things, hackers had managed to hack the network using maliciously encoded file attachments.
The reason why they had actually blocked users from sending and receiving attachments in the unclassified network was to give their technicians sufficient time to scan the network and identify and eradicate all threats.
Malicious attachments can be dangerous for your computer Coincidentally, Microsoft had warned about attackers sending malicious attachments in QuickTime media files to innocent victims.
This was done with the intention of exploiting the un-patched flaws of Apple's media format to make it possible to install malicious software on Windows systems which is very detrimental o all machines.
While the FBI outage was the first report of such outages by the New York Post, other news outlets had reported last week about the FBI getting attacked by the same virus that had attacked the Windows systems of the US Marshal's.