One of America's largest auto dealers says the IT outage caused by CDK Global's ransomware attack in June cost about $30 million.

Sonic Automotive filed a Form 8-K with the Securities and Exchange Commission (SEC) on Monday alongside the release of its quarterly reports, confirming that it, like its competitors, was significantly affected by the incident at CDK.

Of the total $30 million decline in GAAP pretax earnings, $11.6 million of that was related to additional compensation paid to staff, and possibly outside contractors, who helped manage the outage, it said.

However, the outfit was still profitable, although the overall loss diluted earnings per share by $0.64 — a significant hit to the $1.18 it would have been without the incident — and that's not "taking into account any recoveries related to to the Incident and after takes into account estimated lost revenue and expenses attributable to the Incident," the 8-K states.