On Thursday, NBC News published a memo from the NSA, reporting that an unnamed civilian employee of the agency had been linked to leaks made by former NSA contractor Edward Snowden.

The employee, the memo said, allowed Snowden to use his “Public Key Infrastructure (PKI) certificate to access classified information on NSANet; access that he knew had been denied to Mr. Snowden.” The NSA further alleges that Snowden asked the employee to enter his PKI password on Snowden's computer, on which he “was able to capture the password” without the employee's knowledge.

“The civilian was not aware that Mr. Snowden intended to unlawfully disclose classified information,” read the memo. "However, by sharing his PKI certificate, he failed to comply with security obligations." The employee had his security clearance revoked in November and resigned in January.

The memo was addressed to congressional intelligence and judiciary committees and was sent February 10. The New York Times notes that the memo was intended to respond to the committees' questions about accountability for the security lapses that allowed Snowden so much access within the NSA's system. “The answer appeared to suggest that no senior officials of the NSA or its oversight organization, the office of the director of national intelligence, will be disciplined or fired for what officials have called the largest and most damaging disclosure of classified material in American history,” wrote the Times.

Back in November, Reuters sources said that Snowden convinced “20 to 25” of his coworkers to give him their login credentials. So far, however, only three people have been disciplined—the civilian NSA employee, as well as an active duty military member and another contractor. The two latter were not employees of the NSA, so while their access to NSA information was revoked, their employers are responsible for disciplinary action.