The House of Representatives' Republican campaign organisation was the target of a major hack during the 2018 election that exposed thousands of sensitive emails, a news report said on Tuesday.
"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, one of the firms the GOP hired to address the breach.
The statement did not provide additional details about the incident, but added the security of the committee's data is of paramount concern.
Rep. Steve Stivers (R-Ohio), the House member in charge of the committee during the 2018 cycle, did not respond to Politico's repeated requests for comment.
The breach, which was discovered in April, was only reportedly known by high-level party officials and some Republican lawmakers. "It's time to wake up", Warner said. "I heard they were trying to hack the Republicans, too".
In August, Microsoft alerted the public to attempts by government-backed Russian hackers to target US conservatives' email by creating fake websites that appeared to belong a pair of think tanks, the Hudson Institute and International Republican Institute. Claire McCaskill, the Missouri Democrat who lost a re-election bid in November.
CrowdStrike was previously the source of the claims that rogue Russian hackers invaded the Democratic National Committee's (DNC) servers.
Although it is unclear who was behind the hack, several officials privately believe it may have been the work of foreign hackers. The emails were obtained after Hillary Clinton's campaign chair John Podesta fell for a phishing scam and were posted by Wikileaks. That included IL, where records on 90,000 voters had been downloaded. None of the emails accessed have been released to the public, nor were NRCC officials threatened by the perpetrators with such an action. DHS is the lead agency in charge of election cybersecurity efforts. There had been a major push since the midterms to shore up defenses against potential cyber intrusions, but most states remained highly vulnerable.