Mastercard PayPass — EMVCo Kernel 2
Mastercard PayPass (Kernel 2) contactless: no TTQ, CDA offline authentication, on-device CDCVM, mag-stripe legacy path and data storage.
Overview
Kernel 2 is the EMVCo contactless kernel for Mastercard PayPass. Unlike Visa/Discover/UnionPay it does not exchange a Terminal Transaction Qualifiers (9F66) object — reader capabilities and limits are configured through the standard terminal-capability tags and the proprietary DF81xx reader tags.
It authenticates the card with Combined Dynamic Data Authentication (CDA), where the dynamic signature is produced together with the cryptogram at GENERATE AC, and it supports on-device cardholder verification (CDCVM) for mobile wallets.
Transaction flow
Mastercard PayPass (Kernel 2) contactless processing. Kernel 2 does not use a TTQ — it relies on Combined DA (CDA), supports a mag-stripe legacy path, and can perform on-device CDCVM and data storage.
1Combination Selection
PPSE → AID
Entry Point reads the PPSE and selects a card combination (AID + kernel). Kernel 2 is activated for Mastercard contactless.
No TTQ — reader capabilities via standard tags
Kernel 2 does not use tag 9F66. Reader capability and CVM limits come from Terminal Capabilities (9F33), Additional Terminal Capabilities (9F40), and the proprietary reader tags DF8117 (floor limit), DF8118 (CVM-required limit) and DF8119 (no-CVM transaction limit).
Cardholder verification
CVM follows the card CVM list combined with the Mobile Support / on-device indicators: mobile wallets confirm CDCVM on-device, otherwise online PIN or signature is selected.
Key data elements
| Tag | Name | Notes |
|---|---|---|
9F5D | Application Capabilities Information | Mastercard meaning of 9F5D (UnionPay uses the same tag for Available Offline Spending Amount). |
9F6D | Mag-stripe Application Version Number (Reader) | Reader-side mag-stripe version indicator. |
9F6E | Third Party Data | Mastercard meaning of 9F6E. |
DF8117 | Reader Contactless Floor Limit | Proprietary Book C-2 reader configuration tag. |