Contacts for misdirected payments and user authentication

1. A method comprising:

receiving, by a payment service system (PSS) and from a payment application executing on a device of a sender, a payment request including a recipient identifier corresponding to a recipient, wherein the sender and recipient have respective financial accounts associated with the PSS, the device of the sender having encrypted contact records of the sender stored thereon and shared with the PSS;

performing, at the device of the sender, a first authentication process to determine that there is no match for the recipient identifier in the encrypted contact records stored locally on the device of the sender;

receiving, at the PSS and from the device of the sender, a notification of the first authentication process performed on the device of the sender;

upon receiving the notification, performing, by the PSS, a second authentication process, wherein the second authentication process is different than the first authentication process performed on the device of the sender and the second authentication process compares encrypted contact records of the sender and encrypted contact records of the recipient to determine a similarity score between the sender and the recipient identified in the payment request, wherein the encrypted contact records of the sender and the encrypted contact records of the recipient are stored in a database communicatively coupled to the PSS; and

authorizing, by the PSS, a payment transaction associated with the payment request based at least in part on (i) a determination that the similarity score satisfies a threshold or (ii) upon receiving an approval of the recipient from the device.

2. The method of claim 1 , wherein each contact record of the encrypted contact records of the sender and the encrypted contact records of the recipient are assigned a weighted value; and

determining the similarity score includes calculating a summation of weighted values associated with the encrypted contact records of the sender and the encrypted contact records of the recipient.

3. The method of claim 2 , wherein the weighted value assigned to a contact record of the encrypted contact records of the sender and the encrypted contact records of the recipient is based at least in part on frequency of association of the contact record with the sender or the recipient.

4. The method of claim 1 , wherein the similarity score is further determined based at least in part on a degree of separation between the encrypted contact records of the sender and the encrypted contact records of the recipient.

5. The method of claim 1 , where the similarity score is based on contact records associated with the encrypted contact records stored on the device of the sender, wherein the PSS determines whether the recipient identifier corresponds to a contact record associated with the encrypted contact records.

6. The method of claim 1 , further comprising:

based at least in part on a determination that the similarity score does not satisfy the threshold, transmitting a request to the device of the sender to confirm an identity of the recipient, wherein the approval from the device of the sender is received in response to the request.

7. The method of claim 1 , wherein each of the encrypted contact records on the device of the sender comprises a corresponding hash value generated by the device of the sender according to a hash function.

8. The method of claim 1 , further comprising:

storing one or more hash values representing encrypted contact records of the sender;

storing one or more hash values representing encrypted contact records of the recipient; and

responsive to receiving the notification from the device of the sender, retrieving the one or more hash values representing the encrypted contact records of the recipient based at least in part on the recipient identifier.

9. The method of claim 8 , wherein determining the similarity score comprises:

comparing the one or more hash values representing the encrypted contact records of the sender and the one or more hash values representing the encrypted contact records of the recipient.

10. The method of claim 1 , wherein the encrypted contact records on the device of the sender comprise one or more identifiers for a contact associated with a previous payment request associated with the recipient.

11. The method of claim 1 , wherein authorizing the payment transaction associated with the payment request comprises:

transmitting a message indicating approval of the payment transaction to a system of record server.

12. One or more non-transitory computer-readable media comprising computer-readable instructions, which when executed by one or more processors of a payment service system, cause the one or more processors to:

receive, at a payment processing server, a payment request from a payment application executing on a device of a sender, the payment request including a recipient identifier corresponding to a recipient, wherein the sender and recipient have respective financial accounts associated with the payment service system, the device of the sender having encrypted contact records of the sender stored thereon and shared with the payment service system;

perform, at the device of the sender, a first authentication process to determine that there is no match for the recipient identifier in the encrypted contact records stored locally on the device of the sender;

receive, at the payment processing server and from the device of the sender, a notification of the first authentication process performed on the device of the sender;

upon receiving the notification, performing, by the payment service server, a second authentication process, wherein the second authentication process is different than the first authentication process performed on the device of the sender and the second authentication process compares encrypted contact records of the sender and encrypted contact records of the recipient to determine a similarity score between the sender and the recipient identified in the payment request, wherein the encrypted contact records of the sender and the encrypted contact records of the recipient are stored in a database communicatively coupled to the payment service system; and

authorize a payment transaction associated with the payment request based at least in part on (i) a determination that the similarity score satisfies a threshold or (ii) upon receiving an approval of the recipient from the device.

13. The one or more non-transitory computer-readable media of claim 12 , wherein the similarity score is determined based on at least one of the encrypted contact records of the sender or encrypted contact records of the recipient.

14. A system comprising:

a device associated with a sender, wherein the device associated with the sender is configured to perform a first authentication process to determine that there is no match for a recipient identifier in encrypted contact records stored locally on the device associated with the sender; and

a payment processing server, wherein the payment processing server is configured to:

receive a payment request from a payment application executing on the device associated with the sender, the payment request including the recipient identifier corresponding to a recipient, wherein the sender and recipient have respective financial accounts associated with a payment service system, the device associated with the sender having encrypted contact records of the sender stored thereon and shared with the system;

receive, from the device of the sender, a notification of the first authentication process performed on the device of the sender;

upon receiving the notification, performing, a second authentication process, wherein the second authentication process is different than the first authentication process performed on the device of the sender and the second authentication process compares encrypted contact records of the sender and encrypted contact records of the recipient to determine a similarity score between the sender and the recipient identified in the payment request, wherein the encrypted contact records of the sender and the encrypted contact records of the recipient are stored in a database communicatively coupled to the system; and

authorize a payment transaction associated with the payment request based at least in part on (i) a determination that the similarity score satisfies a threshold or (ii) upon receiving an approval of the recipient from the device associated with the sender if the similarity score does not satisfy the threshold.

15. The method of claim 1 , further comprising:

authenticating the device of the sender based at least in part on the encrypted contact records associated with the device of the sender, upon receiving the payment request and prior to determining the similarity score.

16. The one or more non-transitory computer-readable media of claim 12 , wherein the execution of the computer-readable instructions by the one or more processors, cause the one or more processors to:

authenticate the device of the sender based at least in part on the encrypted contact records associated with the device of the sender, upon receiving the payment request and prior to determining the similarity score.

17. The system of claim 14 , wherein the payment processing server is configured to determine the similarity score based on at least one of the encrypted contact records of the sender and encrypted contact records of the recipient.

18. The method of claim 1 , wherein the first authentication process determines that there is no match for the recipient identifier in the encrypted contact records stored locally on the device of the sender by one of:

determining that the recipient identifier does not match any contacts stored on the device of the sender; or

determining that the recipient identifier is not on a list of recipients associated with a prior payment history on the device of the sender.

19. The one or more non-transitory computer-readable media of claim 12 , wherein the execution of the computer-readable instructions by the one or more processors, cause the one or more processors to determine that there is no match for the recipient identifier in the encrypted contact records stored locally on the device of the sender by one of:

determining that the recipient identifier does not match any contacts stored on the device of the sender; or

determining that the recipient identifier is not on a list of recipients associated with a prior payment history on the device of the sender.

20. The system of claim 14 , wherein the device associated with the sender is configured to determine that there is no match for the recipient identifier in the encrypted contact records stored locally on the device of the sender by one of:

determining that the recipient identifier does not match any contacts stored on the device of the sender; or

determining that the recipient identifier is not on a list of recipients associated with a prior payment history on the device associated with the sender.