VeriSign, the generic top-level domain that administers .com, .net and org, was hacked several times in 2010, according to its financial filings.
"In 2010, the Company faced several successful attacks against its corporate network in which access was gained to information on a small portion of our computers and servers," the company reported in a filing lodged with the Securities and Exchange Commission in October 2011.
News agency Reuters, which first reported the disclosure, noted that a compromise of VeriSign's domain name system (DNS) servers could allow an attacker to redirect people to a malicious web page or intercept corporate and government email.
VeriSign claims its DNS systems were not affected, however it has not disclosed which systems were affected by the breaches.
"We have investigated and do not believe these attacks breached the servers that support our Domain Name System (“DNS”) network."
It did however confirm that "information stored on the compromised corporate systems was exfiltrated."
If the affected systems include its Secure Sockets Layer (SSL) certificate business, which it sold to Symantec in August 2010, it could represent one of the largest compromises of the system that regulates trust on the web.
Dutch certificate authority DigiNotar was hacked last year, leading to over 200 fraudulently issued certificates. The breach led to hundreds of thousands of Iranians being redirected to an incorrect IP address when they typed in a domain name like "google.com".
Symantec told Reuters that there was "no indication" Verisign's reported breach was related to its SSL production systems.
That transaction occurred prior to the breach at SSL certificate authority Comodo, and the subsequent breach of Dutch CA DigiNotar, with the latter target facing criticism for failing to disclose the breach after it became aware of it.