Claims follow Bloomberg allegations that the agency exploited flaw in OpenSSL to gather information.
The White House and US intelligence agencies have denied claims that the National Security Agency (NSA) or any other government units were either aware or have exploited the Heartbleed bug in order to collect intelligence.
The denial comes after report from Bloomberg News, citing two sources, claimed that the NSA exploited the flaw in OpenSSL to gather information on citizens.
White House National Security Council spokeswoman Caitlin Hayden said in a statement that reports that NSA or any other part of the government were aware of the so-called Heartbleed vulnerability before April 2014 were incorrect.
"This administration takes seriously its responsibility to help maintain an open, interoperable, secure and reliable Internet," Hayden said.
"If the federal government, including the intelligence community, had discovered this vulnerability prior to last week, it would have been disclosed to the community responsible for OpenSSL."
Upon the discovery of Heartbleed by researchers at Google and Finnish security firm Codenomicon, the US Homeland Security Department advised businesses to check their servers to see if they had been using vulnerable versions of OpenSSL.
In a statement, the NSA said that it was, "not aware of the recently identified vulnerability in OpenSSL, the so-called Heartbleed vulnerability, until it was made public in a private-sector cybersecurity report."
In addition, US banks and other financial institutions have been advised to patch their computers to thwart attacks that exploit the Heartbleed flaw in Internet security.