Threat Management

Library of Congress systems back to normal after four-day DDoS attack

After a four-day long DDoS assault, the Library of Congress announced its computer systems have returned to normal.

The attack disrupted services and websites including, the U.S. Copyright Office, the BARD service, library data bases and both incoming and outgoing email, according to a July 20 blog post.

Officials said the attack was a massive and sophisticated DNS assault which employed multiple forms of attack and was able to adapt and change on the fly.

“We're satisfied that we've fended off the attack and fortified our system for now, but we'll continue to be vigilant and employ state-of-the-art security systems to effectively respond to these type of incidents in the future,” the blog said.

Officials said there may be residual issues on parts of the library's systems and that problems should be reported via the website's comment form.

Get daily email updates

SC Media's daily must-read of the most current and pressing daily news

By clicking the Subscribe button below, you agree to SC Media Terms and Conditions and Privacy Policy.