The U.S. Census Bureau confirmed Friday it is investigating a breach of one of its computer systems after the hacktivist group Anonymous claimed it had hacked the agency and posted some personal information online.
"Earlier this week, the Census Bureau experienced an attack to gain access to the Federal Audit Clearinghouse, which is housed on an externally facing IT system that contains non-confidential information, such as names of the person submitting the information, organization addresses and phone numbers, site user names, etc.," Census Bureau Director John H. Thompson wrote in a blog post. "While our IT forensics investigation continues, I want to assure you that at this time every indication is that the breach was limited to this database, and that it did not include personally identifiable information provided by people responding to our censuses and surveys."
Thompson said the Federal Audit Clearinghouse collects audit data from state and local governments, non-profit organizations and Indian tribes on how they're spending federal awards.
On Wednesday, Anonymous tweeted that it hacked a subsite of census.gov and posted four links to the information it said it stole. The information leaked online appears to include the names, email addresses and other identifying data of some employees.
"The hackers acquired the data illegally, but as I indicated above, the Clearinghouse site does not store any confidential household or business data collected by the Census Bureau," Thompson said. "That information remains safe, secure and on an internal network segmented apart from the external site and the affected database."
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He said the agency is increasing the security of its site.
The hack comes after the U.S.Office of Personnel Management disclosed in April and May that it was the victim of two massive data breaches that compromised the personal data of more than 22 million people. Fallout from the breaches led to the resignation of Katherine Archuleta as OPM chief.