ISO/IEC 39794-2:2023/Amd 1:2026

ISO/IEC 39794-2:2023/Amd 1:2026 is an ISO amendment to the finger minutiae data part of the extensible biometric data interchange formats series, published by ISO. It specifies how the on-card biometric comparison format is handled for fingerprint minutiae data, including default minutiae counts for enrolment and verification. The amendment is aimed at people designing, implementing, or testing biometric cards and matching systems.

What does ISO/IEC 39794-2:2023/Amd 1:2026 specify?

ISO/IEC 39794-2:2023/Amd 1:2026 adds handling guidance for the on-card biometric comparison format to ISO/IEC 39794-2. In practice, it gives implementers a common basis for how many minutiae may be used, how comparison conditions are interpreted, and what security points matter when minutiae are sent to a card.

The amendment updates subclause 8.3.1, updates subclause 8.3.9.1, and adds informative Annex E. It also adds two bibliography entries: one for the MINEX II evaluation plan and one for ISO/IEC 7816-4.

What are the key requirements of ISO/IEC 39794-2:2023/Amd 1:2026?

ISO/IEC 39794-2:2023/Amd 1:2026 focuses on minutiae counts, comparison conditions, retry control, and communication security for on-card biometric comparison. The main practical point is that a card and its surrounding system have to agree on how much biometric detail is expected, how matching is judged, and how repeated attempts are limited.

Minutiae counts for enrolment and verification

Subclause 8.3.9.1 sets default values for the minimum number of minutiae required for enrolment and verification, and for the receivable maximum number of minutiae. Annex E explains why these values matter: too few minutiae can prevent enrolment or cause rejection because the probe data is insufficient, while too many can affect transmission time, memory use, execution time, and security.

Handling of the on-card comparison format

Subclause 8.3.1 adds a pointer to Annex E for using on-card biometric comparison formats. Annex E.2 says the biometric probe data may be affected by translation in X and Y, rotation, and distortion, so the decision threshold has to take the required FAR and FRR into account. In practice, matching parameters cannot be chosen in isolation from the capture conditions and the security target.

Enrolment process controls

Annex E.1 says the number of minutiae is a security-sensitive parameter and depends on the application security policy. Annex E.1.2 says the number of required finger presentations during enrolment is system dependent. For implementers, this means enrolment logic, capture quality, and policy settings all influence whether a person can be enrolled.

Retry counter for verification

Annex E.2.2 requires a retry counter for on-card comparison to limit the number of trials. Negative verifications decrement the counter, positive verification resets it, and the biometric method is blocked when the counter reaches zero. The annex recommends an initial value between 5 and 15, which helps designers balance user convenience against attack resistance.

Security aspects of sending minutiae to the card

Annex E.3 warns about replay attacks if biometric probes are accepted in plain text without digital signature, cryptogram, or prior authentication between the interface device and the ICC. It also points to secure messaging as a common trusted-path approach and notes the risk of latent fingerprints on the card surface. For users of the standard, this means transport security and card handling policy are part of the overall biometric design.

What terms does ISO/IEC 39794-2:2023/Amd 1:2026 define?

ISO/IEC 39794-2:2023/Amd 1:2026 uses a small set of operational terms that matter for card enrolment and matching.

• Biometric probe data - the fingerprint minutiae data presented for comparison against the stored reference.
• Biometric reference - the stored biometric data used as the match target.
• False match rate (FAR) - the rate that a comparison incorrectly accepts a non-matching probe.
• False non-match rate (FRR) - the rate that a comparison incorrectly rejects a matching probe.
• Integrated circuit card (ICC) - the card that performs or supports on-card biometric comparison.
• Retry counter - a counter that limits repeated verification attempts by decreasing on negative results and resetting on positive results.
• Security policy - the application rules that set the acceptable biometric and operational limits.

Who uses ISO/IEC 39794-2:2023/Amd 1:2026?

ISO/IEC 39794-2:2023/Amd 1:2026 is used by developers of fingerprint-on-card systems, biometric algorithm suppliers, smart card and ICC integrators, and application providers. It is also relevant to interoperability test labs and teams that set FAR and FRR targets or choose retry limits for enrolment and verification. In practice, it helps the people who must align the card, the sensor, the matching software, and the security policy.

What changed in ISO/IEC 39794-2:2023/Amd 1:2026 from the previous edition?

ISO/IEC 39794-2:2023/Amd 1:2026 is Amendment 1 to ISO/IEC 39794-2:2023. It adds handling for the on-card biometric comparison format, updates subclause 8.3.1, adds default minutiae values in subclause 8.3.9.1, introduces informative Annex E, and adds bibliography entries for MINEX II and ISO/IEC 7816-4.

Which standards are used with ISO/IEC 39794-2:2023/Amd 1:2026?

ISO/IEC 39794-2:2023/Amd 1:2026 works with related ISO/IEC documents named in the amendment.

• ISO/IEC 39794-2 - the base finger minutiae data standard that this amendment updates.
• ISO/IEC 7816-4 - contributes the RESET RETRY COUNTER command and the secure messaging context used in Annex E.
• ISO/IEC 24787 - provides the on-card biometric comparison context referenced in Annex E.

What does the ISO/IEC 39794-2:2023/Amd 1:2026 document contain?

ISO/IEC 39794-2:2023/Amd 1:2026 contains short amendments to subclauses 8.3.1 and 8.3.9.1 and a new informative Annex E. Annex E covers enrolment, comparison, retry counter handling, and security aspects of sending finger minutiae probe data to the card. It also adds bibliography references that support evaluation of fingerprint match-on-card performance and the use of ISO/IEC 7816-4 commands and secure messaging.