Flutter Square InApp Payments SSL Handshake and Security Check Error

[tchuong2ca]

I am integrating Square In-App Payments using the square_in_app_payments library version 1.7.12 with the Flutter framework, and I am testing in the production environment.

Test devices:

• iOS: iPhone 13

• Android: Xiaomi Mi 10S

Test card information:

• Card type: Visa

• Issuing bank: Vietcombank (VCB)

• Country: Vietnam

Observed behavior:

• Visa cards issued by other banks work normally in the same production environment.

• When entering the Vietcombank Visa card details (card number, expiration date, CVV) and tapping Save, a popup with the Visa logo appears, indicating that the payment flow has started and is attempting to connect to the card issuer / bank for authentication.

• Shortly after this popup appears, the process fails with the following errors:

On iOS:

• “Something went wrong. Please contact the developer of this application and provide them with this error code: unexpected”
  or

• “Could not establish SSL handshake. Error code: [204]”

On Android:

• “Device has failed the internal security checks. If you are testing on an Android Emulator, please switch to the Sandbox environment. Failed checks: [Warning(id=SW02, message=The integrity of the SDK has been tampered., severity=HIGH)]”
  or

• “Could not establish SSL handshake. Error code: [204]”

Additional details:

• After the “Device has failed the internal security checks” error occurs, subsequent attempts to save other cards also fail with the same error.

• If the Vietcombank Visa card is not entered first, other Visa cards can be saved and charged successfully.

• This state persists until the app is restarted.