James Cartwright entered the plea at a hearing Monday before U.S. District Judge Richard Leon.
The U.S. attorney's office in Maryland announced the case on Monday.
According to a court document, Mr. Cartwright in November 2012 "falsely told investigators that he was not the source of any of the quotes and statements" in Mr. Sanger's book.
In the new case, Mr. Cartwright is accused of lying to investigators about conversations with two journalists, David Sanger of the New York Times and Daniel Klaidman, then working at Newsweek and now deputy editor of Yahoo News.
After pleading guilty to attempting to mislead the Federal Bureau of Investigation probe, Cartwright said: "I knew I was not the source of the story, and I didn't want to be blamed for the leak". He added, "I love my country and continue to this day to do everything I can to defend it". Craig's office said he would issue a statement later Monday.
I think the reality is that this trend will not stop leaking. The government did not reveal the title of Sanger's book.
"People who gain access to classified information after promising not to disclose it must be held accountable when they willfully violate that promise", said U.S. Attorney Rosenstein. White House officials, for instance, did not want to declassify material that would be important to the case. "This was a careful, rigorous, and thorough multi-year investigation by special agents who, together with federal prosecutors, conducted numerous interviews, to including Cartwright". That gave prosecutors the grounds to bring the felony charge. The forms also contain warnings that any breach of the agreement may violate federal criminal law.
Still, the former official said, "if you talk and lie, it's much worse than not talking".
The evidence showed that General Cartwright disclosed classified information without authorization to two reporters and lied to federal investigators. Obama said he had zero tolerance for such leaks.
Based on the plea deal worked out between the retired general and the government, Cartwright only faces charges for misleading investigators-not for the leak.
"I think the reality is that this trend will not stop leaking", Vladeck said. It was later reported that one of these investigations focused on the secret Operation Olympic Games.
Washington and the world were rocked by Confront and hide, which goes deep into the Situation Room as Obama questions whether this new weapon can slow Iran and avoid a war - or whether it will create blowback, as the Iranians and others retaliate with cyberattacks on the United States.
Mr. Cartwright, 67 years old, served as vice chairman of the Joint Chiefs of Staff from 2007 until 2011.
The court documents don't indicate which alleged discussions between Mr. Cartwright and Mr. Klaidman were part of the investigation, but in 2012 Mr. Klaidman wrote an article about US efforts regarding the Iranian nuclear program.
Iran has publicly blamed the United States and Israel for the computer virus, but neither country has officially acknowledged a role in the attack.
Disclosures about the operation set off a political controversy, with congressional Republicans charging that the White House had deliberately leaked information to enhance Obama's national security credentials as he sought reelection.