Verisign, the firm that manages the .com domain, has admitted it was the victim of several cyber attacks in 2010.
Verisign gave notice of the breaches to the US Securities and Exchange Commission (SEC) in September.
In the notice, the firm said management were not informed of the attacks until September 2011.
"The occurrences of the attacks were not sufficiently reported to the company's management at the time they occurred for the purpose of assessing any disclosure requirements," it said.
Verisign also said it doesn't know what data was accessed by hackers, but stated it does not believe the servers supporting the domain name system (DNS) were breached.
"We have investigated and do not believe these attacks breached the servers that support our domain name system network," the submission stated.
This is the system that maps IP addresses to the text addresses internet users employ to find and recognise websites.
Verisign made the report in order to conform to SEC data breach disclosure rules.
The firm said it experienced "security breaches in the corporate network in 2010, which were not sufficiently reported to management".
It added that hackers obtained access to information on a small portion of the firm's computers and servers, and that there is evidence data left the company in this breach.
According to the SEC filing, Verisign's security team took defensive measures to prevent further attacks shortly after they occurred.
"The company's information security group was aware of the attacks shortly after the time of their occurrence, and the group implemented remedial measures designed to mitigate the attacks and detect and thwart similar additional attacks."
The firm also warned that future attacks are still possible, despite these counter-measures.
"We cannot assure our remedial actions will be sufficient to thwart future attacks or prevent the loss of information."
Have your say on this article
Newsletters
Latest stories from Security
Latest videos
You may also like
Security jobs
Technology Patent Wars
Case studies from large organisations across all sectors
... And rich media, and flexible working, and peaks in traffic ...
Upcoming Events
Join us for this Computing web seminar, in which the Head of BI at the Co-operative Group Nick Colebourn will be explaining just how he reigned in the Group’s sprawling database estate and how significant savings were realised and data quality improved as a result.
Date: 31 May 2012
Time: 11:00 AM
Live June 13th 11:00am: Register now. During this web seminar we will be looking at the sorts of incidents that can bring data centres grinding to a halt and what can be done about them.
Date: 13 Jun 2012
Time: 11:00 am
Receive the latest jobs direct to your inbox
Are you being paid what you are worth?