President Trump (YouTube screenshot)

President Trump (YouTube screenshot)

The email accounts of four senior aides at the GOP House campaign arm were hacked during the 2018 election.

Thousands of sensitive emails by members of the National Republican Congressional Committee were exposed to an outside intruder, reported Politico, citing three senior party officials.

The party officials said the email traffic was surveilled for several months.

Politico reported the intrusion was detected in April by an NRCC vendor and reported to the committee, which alerted the FBI.

But senior and rank-and-file House Republicans, including Speaker Paul Ryan, R-Wis., were not informed of the hack until Politico contacted the NRCC on Monday.

Committee officials told Politico they withheld the information because they feared revealing the hack would compromise their internal investigation’s effort to find the culprit.

“We don’t want to get into details about what was taken because it’s an ongoing investigation,” a senior party official told Politico. “Let’s say they had access to four active accounts. I think you can draw from that.”

Politico said party officials privately believe the hacker was a foreign agent, due to the nature of the attack.

They said the hack did not compromise donor information.

“The NRCC can confirm that it was the victim of a cyber intrusion by an unknown entity,” said Ian Prior, a vice president at Mercury Public Affairs, which was hired by the committee to oversee the response to the hack. “The cybersecurity of the Committee’s data is paramount, and upon learning of the intrusion, the NRCC immediately launched an internal investigation and notified the FBI, which is now investigating the matter.”

Politico noted that in July, President Trump chastised the Democratic National Committee for being hacked.

“The DNC should be ashamed of themselves for allowing themselves to be hacked. They had bad defenses, and they were able to be hacked,” Trump told CBS News. “I heard they were trying to hack the Republicans, too. But, and this may be wrong, but they had much stronger defenses.”

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