Since a cyberattack paralyzed 15,000 auto dealerships nationwide last week, a clearer understanding of the damage has emerged. Several of the largest US dealers are now detailing the potential "material" impact on their finances in regulatory filings since their backend operating systems, managed by CDK Global, went down early last week. 

Bloomberg reports Sonic Automotive Group, Group 1 Automotive, AutoNation, Lithia Motors, and Asbury Automotive Group have filed disclosures with the US Securities and Exchange Commission in recent days, specifying that their backend management systems, powered by CDK, have been disrupted since the cyber incident, negatively impacting their business.

The incident "has had, and is likely to continue to have, a negative impact," Sonic wrote in the SEC filing. 

Here's more color on what auto dealers are saying in the filings (courtesy of Bloomberg):

Shares of Sonic, Group 1, AutoNation, Lithia, and Asbury have all declined between 1.5% and 5% since the ransom attack, in which Bloomberg said the cyber gang involved was BlackSuit and demanded millions of dollars from CDK. 

X users Car Dealership Guy reports Tuesday afternoon, "Dealership outages will continue until at least June 30th." 

But some dealers, such as the Mazda dealership in Seekonk, Massachusetts, where Ryan Callahan, the manager, told CNN: "The financial impact it will directly have on us will take months to correct, if not years."