http://www.washingtonpost.com/blogs/the-switch/wp/2017/09/08/after-data-breach-equifax-asks-consumers-for-social-security-numbers-to-see-if-theyve-been-affected/

After hackers gained access to Equifax files that included sensitive personal data on 143 million Americans, the credit reporting company said Thursday it will offer free credit monitoring services to all U.S. consumers for one year. But before people can sign up and find out whether their personal information was compromised, consumers are prompted to enter their last name and the last six digits of their Social Security number.