Finding Friends with Phone Numbers
Occasionally computer security professionals and other helpful people reach out to us about potential bugs and vulnerabilities in Snapchat. We are grateful for the assistance of professionals who practice responsible disclosure and we’ve generally worked well with those who have contacted us.
This week, on Christmas Eve, a security group posted documentation for our private API. This documentation included an allegation regarding a possible attack by which one could compile a database of Snapchat usernames and phone numbers.
Our Find Friends feature allows users to upload their address book contacts to Snapchat so that we can display the accounts of Snapchatters who match the phone numbers found in the address book. Adding a phone number to your Snapchat account is optional, but it’s helpful for allowing your friends to find you. We don’t display the phone numbers to other users and we don’t support the ability to look up phone numbers based on someone’s username.
Theoretically, if someone were able to upload a huge set of phone numbers, like every number in an area code, or every possible number in the U.S., they could create a database of the results and match usernames to phone numbers that way. Over the past year we’ve implemented various safeguards to make it more difficult to do. We recently added additional counter-measures and continue to make improvements to combat spam and abuse.