A group that claims to have hacked CDK Global, the software provider to thousands of car dealerships in North America, has demanded tens of millions of dollars in ransom, according to a person familiar with the matter.CDK is planning to make the payment, said the person, who asked not to be identified because the information is private. The hacking group behind the attack is believed to be based in eastern Europe, the person said. In the early days of any ransomware attack, discussions are fluid...