MIFARE

The MIFARE Classic IC is just a memory storage device, where the memory is divided into segments and blocks with simple security mechanisms for access control. They are ASIC-based and have limited computational power. Due to their reliability and low cost, those cards are widely used for electronic wallets, access control, corporate ID cards, transportation or stadium ticketing. It uses an NXP proprietary security protocol (Crypto-1) for authentication and ciphering.

MIFARE Classic encryption has been compromised; see below for details.

The MIFARE Classic with 1K memory offers 1,024 bytes of data storage, split into 16 sectors; each sector is protected by two different keys, called A and B. Each key can be programmed to allow operations such as reading, writing, increasing value blocks, etc. MIFARE Classic with 4K memory offers 4,096 bytes split into forty sectors, of which 32 are the same size as in the 1K with eight more that are quadruple size sectors. MIFARE Classic Mini offers 320 bytes split into five sectors. For each of these IC types, 16 bytes per sector are reserved for the keys and access conditions and can not normally be used for user data. Also, the very first 16 bytes contain the serial number of the card and certain other manufacturer data and are read-only. That brings the net storage capacity of these cards down to 752 bytes for MIFARE Classic with 1K memory, 3,440 bytes for MIFARE Classic with 4K memory, and 224 bytes for MIFARE Mini.

The Samsung TecTile NFC tag stickers use MIFARE Classic chips. This means only devices with an NXP NFC controller chip can read or write these tags. At the moment BlackBerry phones, the Nokia Lumia 610 (August 2012[4]), the Google Nexus 4, Google Nexus 7 LTE and Nexus 10 (October 2013[5]) can't read/write TecTile stickers.

MIFARE Plus is a replacement IC solution for the MIFARE Classic.

Key applications:

• Public transportation
• Access management; e.g., employee, school, or campus cards
• Electronic toll collection
• Car parking
• Loyalty programs

It is less flexible than a MIFARE DESFire EV1 contactless IC.

MIFARE Plus was publicly announced in March 2008 with first samples in Q1 2009.[6]

MIFARE Plus, when used in older transportation systems that do not yet support AES on the reader side, still leaves an open door to attacks. Though it helps to mitigate threats from attacks that broke the Crypto-1 cipher through the weak random number generator, it does not help against brute force attacks and cryptoanalytic attacks.[7]

During the transition period from MIFARE Classic to MIFARE Plus where only a few readers might support AES in the first place, it offers an optional AES authentication in Security Level 1 (which is in fact MIFARE Classic operation). This does not prevent the attacks mentioned above but enables a secure mutual authentication between the reader and the card to prove that the card belongs to the system and is not fake.

In its highest security level SL3, using 128-bit AES encryption, MIFARE Plus is secured from attacks.

MIFARE Plus EV1 was announced in April 2016.[8]

New features compared to MIFARE Plus X include:

Sector-wise security-level switching

The choice of crypto algorithm used in the authentication protocol can be set separately for each sector. This makes it possible to use the same card with both readers that can read MIFARE Classic products (with sectors protected by 48-bit CRYPTO1 keys, "Security Level 1") and readers that can read MIFARE Plus products (with sectors protected by 128-bit AES keys, "Security Level 3"). This feature is intended to make it easier to gradually migrate existing MIFARE Classic product-based installations to MIFARE Plus, without having to replace all readers at the same time.

ISO 7816-4 wrapping

The card can now be accessed in either the protocol for MIFARE (which is not compliant with the ISO 7816-4 APDU format), or using a new protocol variant that runs on top of ISO 7816-4. This way the cards become compatible with NFC reader APIs that can only exchange messages in ISO 7816-4 APDU format, with a maximum transfer data buffer size of 256 bytes.

Proximity check

While the protocol for MIFARE Classic tolerated message delays of several seconds, and was therefore vulnerable to relay attacks, MIFARE Plus EV1 now implements a basic "ISO compliant" distance-bounding protocol. This puts tighter timing constraints on the permitted round-trip delay during authentication, to make it harder to forward messages to far-away cards or readers via computer networks.

Secure end-2-end channel

Permits AES-protected over-the-air updates even to Crypto1 application sectors (SL1SL3 mix mode).

Transaction MAC

The card can produce an additional message-authentication code over a transaction that can be verified by a remote clearing service, independent of the keys used by the local reader during the transaction.

The MIFARE Plus EV2 was introduced to the market on 23 June 2020.[9] It comes with an enhanced read performance and transaction speed compared to MIFARE Plus EV1.[10]

New features compared to MIFARE Plus EV1 include:

Transaction Timer

To help mitigate man-in-the-middle attacks, the Transaction Timer feature, which is also available on NXP's MIFARE DESFire EV3 IC, makes it possible to set a maximum time per transaction, so it's harder for an attacker to interfere with the transaction.

The MIFARE Ultralight has only 512 bits of memory (i.e. 64 bytes), without cryptographic security. The memory is provided in 16 pages of 4 bytes. Cards based on these chips are so inexpensive that they are often used for disposable tickets for events such as the Football World Cup 2006. It provides only basic security features such as one-time-programmable (OTP) bits and a write-lock feature to prevent re-writing of memory pages but does not include cryptography as applied in other MIFARE product-based cards.

MIFARE Ultralight EV1[11] introduced in November 2012 the next generation of paper ticketing smart card ICs for limited-use applications for ticketing schemes and additional security options. It comes with several enhancements above the original MIFARE Ultralight:

• 384 and 1024 bits user memory product variants
• OTP, lock bits, configurable counters for improved security
• Three independent 24-bit one-way counters to stop reloading
• Protected data access through 32-bit password
• NXP Semiconductors originality signature function, this is an integrated originality checker and is effective cloning protection that helps to prevent counterfeit of tickets. However, this protection is applicable only to "mass penetration of non NXP originated chips and does not prevent hardware copy or emulation of a single existing valid chip"[12]

Applications:

• Limited-use tickets in public transport
• Event ticketing (stadiums, exhibitions, leisure parks)
• Loyalty

Introduced at the Cartes industry trade show in 2008, the MIFARE Ultralight C IC is part of NXP's low-cost MIFARE product offering (disposable ticket). With Triple DES, MIFARE Ultralight C uses a widely adopted standard, enabling easy integration in existing infrastructures. The integrated Triple DES authentication provides an effective countermeasure against cloning.

Key applications for MIFARE Ultralight C are public transportation, event ticketing, loyalty and NFC Forum tag type 2.

It was introduced in 2022.

The MIFARE DESFire (MF3ICD40) was introduced in 2002 and is based on a core similar to SmartMX, with more hardware and software security features than MIFARE Classic. It comes pre-programmed with the general-purpose MIFARE DESFire operating system which offers a simple directory structure and files. They are sold in four variants: One with Triple-DES only and 4 kiB of storage, and three with AES (2, 4, or 8 kiB; see MIFARE DESFire EV1). The AES variants have additional security features; e.g., CMAC. MIFARE DESFire uses a protocol compliant with ISO/IEC 14443-4.[13] The contactless IC is based on an 8051 processor with 3DES/AES cryptographic accelerator, making very fast transactions possible.

The maximal read/write distance between card and reader is 10 centimetres (3.9 in), but the actual distance depends on the field power generated by the reader and its antenna size.

In 2010, NXP announced the discontinuation of the MIFARE DESFire (MF3ICD40) after it had introduced its successor MIFARE DESFire EV1 (MF3ICD41) in late 2008. In October 2011 researchers of Ruhr University Bochum[14] announced that they had broken the security of MIFARE DESFire (MF3ICD40), which was acknowledged by NXP[15] (see MIFARE DESFire security).

First evolution of MIFARE DESFire contactless IC, broadly backwards compatible. Available with 2 kiB, 4 kiB, and 8 kiB non-volatile memory. Other features include:[16]

• Support for random ID.
• Support for 128-bit AES
• Hardware and operating system are Common Criteria certified at level EAL 4+

MIFARE DESFire EV1 was publicly announced in November 2006.

Key applications:

• Advanced public transportation
• Access management
• Loyalty
• Micropayment

The second evolution of the MIFARE DESFire contactless IC family, broadly backwards compatible.[17] New features include:

• MIsmartApp enabling to offer or sell memory space for additional applications of 3rd parties without the need to share secret keys
• Transaction MAC to authenticate transactions by 3rd parties
• Virtual Card Architecture for privacy protection
• Proximity check against relay attacks

MIFARE DESFire EV2 was publicly announced in March 2016 at the IT-TRANS event in Karlsruhe, Germany

The latest evolution of the MIFARE DESFire contactless IC family, broadly backward compatible. New features include:

• ISO/IEC 14443 A 1–4 and ISO/IEC 7816-4 compliant
• Common Criteria EAL5+ certified for IC hardware and software
• NFC Forum Tag Type 4 compliant
• SUN message authentication for advanced data protection within standard NDEF read operation
• Choice of open DES/2K3DES/3K3DES/AES crypto algorithms
• Flexible file structure hosts as many applications as the memory size supports
• Proof of transaction with card generated MAC
• Transaction Timer mitigates risk of man-in-the-middle attacks

MIFARE DESFire EV3 was publicly announced on 2 June 2020.[18]

MIFARE SAMs are not contactless smart cards. They are secure access modules designed to provide the secure storage of cryptographic keys and cryptographic functions for terminals to access the MIFARE products securely and to enable secure communication between terminals and host (backend). MIFARE SAMs are available from NXP in the contact-only module (PCM 1.1) as defined in ISO/IEC 7816-2 and the HVQFN32 format.

Integrating a MIFARE SAM AV2 in a contactless smart card reader enables a design that integrates high-end cryptography features and the support of cryptographic authentication and data encryption/decryption. Like any SAM, it offers functionality to store keys securely and perform authentication and encryption of data between the contactless card and the SAM and the SAM towards the backend. Next to a classical SAM architecture, the MIFARE SAM AV2 supports the X-mode which allows a fast and convenient contactless terminal development by connecting the SAM to the microcontroller and reader IC simultaneously.

MIFARE SAM AV2 offers AV1 mode and AV2 mode where in comparison to the SAM AV1 the AV2 version includes public key infrastructure (PKI), hash functions like SHA-1, SHA-224, and SHA-256. It supports MIFARE Plus and secure host communication. Both modes provide the same communication interfaces, cryptographic algorithms (Triple-DES 112-bit and 168-bit key, MIFARE products using Crypto1, AES-128 and AES-192, RSA with up to 2048-bit keys), and X-mode functionalities. The MIFARE SAM AV3 is the third generation of NXP's Secure Access Module, and it supports MIFARE ICs as well as NXP's UCODE DNA, ICODE DNA and NTAG DNA ICs.[19]

A cloud-based platform that digitizes MIFARE product-based smart cards and makes them available on NFC-enabled smartphones and wearables. With this, new Smart City use cases such as mobile transit ticketing, mobile access and mobile micropayments are being enabled.[20]

The encryption used by the MIFARE Classic IC uses a 48-bit key.[30]

A presentation by Henryk Plötz and Karsten Nohl[31] at the Chaos Communication Congress in December 2007 described a partial reverse-engineering of the algorithm used in the MIFARE Classic chip. Abstract and slides[32] are available online. A paper that describes the process of reverse engineering this chip was published at the August 2008 USENIX security conference.[33]

In March 2008 the Digital Security[34] research group of the Radboud University Nijmegen made public that they performed a complete reverse-engineering and were able to clone and manipulate the contents of an OV-Chipkaart which is using MIFARE Classic chip.[35] For demonstration they used the Proxmark3 device, a 125 kHz / 13.56 MHz research instrument.[36] The schematics and software are released under the free GNU General Public License by Jonathan Westhues in 2007. They demonstrate it is even possible to perform card-only attacks using just an ordinary stock-commercial NFC reader in combination with the libnfc library.

The Radboud University published four scientific papers concerning the security of the MIFARE Classic:

• A Practical Attack on the MIFARE Classic[37]
• Dismantling MIFARE Classic[38]
• Wirelessly Pickpocketing a MIFARE Classic Card[39]
• Ciphertext-only Cryptanalysis on Hardened MIFARE Classic Cards[40]

In response to these attacks, the Dutch Minister of the Interior and Kingdom Relations stated that they would investigate whether the introduction of the Dutch Rijkspas could be brought forward from Q4 of 2008.[41]

NXP tried to stop the publication of the second article by requesting a preliminary injunction. However, the injunction was denied, with the court noting that, "It should be considered that the publication of scientific studies carries a lot of weight in a democratic society, as does inform society about serious issues in the chip because it allows for mitigating of the risks."[42][43]

Both independent research results are confirmed by the manufacturer NXP.[44] These attacks on the cards didn't stop the further introduction of the card as the only accepted card for all Dutch public transport the OV-chipkaart continued as nothing happened[45] but in October 2011 the company TLS, responsible for the OV-Chipkaart announced that the new version of the card will be better protected against fraud.[46]

The MIFARE Classic encryption Crypto-1 can be broken in about 200 seconds on a laptop from 2008,[47] if approx. 50 bits of known (or chosen) keystream are available. This attack reveals the key from sniffed transactions under certain (common) circumstances and/or allows an attacker to learn the key by challenging the reader device.

The attack proposed in[48] recovers the secret key in about 40 ms on a laptop. This attack requires just one (partial) authentication attempt with a legitimate reader.

Additionally, there are a number of attacks that work directly on a card and without the help of a valid reader device.[49] These attacks have been acknowledged by NXP.[50] In April 2009 new and better card-only attack on MIFARE Classic has been found. It was first announced at the rump session of Eurocrypt 2009.[51] This attack was presented at SECRYPT 2009.[52] The full description of this latest and fastest attack to date can also be found in the IACR preprint archive.[53] The new attack improves by a factor of more than 10 all previous card-only attacks on MIFARE Classic, has instant running time, and does not require a costly precomputation. The new attack allows recovering the secret key of any sector of the MIFARE Classic card via wireless interaction, within about 300 queries to the card. It can then be combined with the nested authentication attack in the Nijmegen Oakland paper to recover subsequent keys almost instantly. Both attacks combined and with the right hardware equipment such as Proxmark3, one should be able to clone any MIFARE Classic card in 10 seconds or less. This is much faster than previously thought.

In an attempt to counter these card-only attacks, new "hardened" cards have been released in and around 2011, such as the MIFARE Classic EV1.[54] These variants are insusceptible for all card-only attacks publicly known until then, while remaining backward compatible with the original MIFARE Classic. In 2015, a new card-only attack was discovered that is also able to recover the secret keys from such hardened variants.[55] Since the discovery of this attack, NXP is officially recommending to migrate from MIFARE Classic product-based systems to higher security products.[56]

In November 2010, security researchers from the Ruhr University released a paper detailing a side-channel attack against MIFARE product-based cards.[57] The paper demonstrated that MIFARE DESFire product-based cards could be easily emulated at a cost of approximately $25 in "off the shelf" hardware. The authors asserted that this side-channel attack allowed cards to be cloned in approximately 100 ms. Furthermore, the paper's authors included hardware schematics for their original cloning device, and have since made corresponding software, firmware and improved hardware schematics publicly available on GitHub.[58]

In October 2011 David Oswald and Christof Paar of Ruhr-University in Bochum, Germany, detailed how they were able to conduct a successful "side-channel" attack against the card using equipment that can be built for nearly $3,000. Called "Breaking MIFARE DESFire MF3ICD40: Power Analysis and Templates in the Real World",[59] they stated that system integrators should be aware of the new security risks that arise from the presented attacks and can no longer rely on the mathematical security of the used 3DES cipher. Hence, to avoid, e.g. manipulation or cloning of smart cards used in payment or access control solutions, proper actions have to be taken: on the one hand, multi-level countermeasures in the back end allow to minimize the threat even if the underlying RFID platform is insecure," In a statement[60] NXP said that the attack would be difficult to replicate and that they had already planned to discontinue the product at the end of 2011. NXP also stated "Also, the impact of a successful attack depends on the end-to-end system security design of each individual infrastructure and whether diversified keys – recommended by NXP – are being used. If this is the case, a stolen or lost card can be disabled simply by the operator detecting the fraud and blacklisting the card, however, this operation assumes that the operator has those mechanisms implemented. This will make it even harder to replicate the attack with a commercial purpose."

In September 2012 a security consultancy Intrepidus[61] demonstrated at the EU SecWest event in Amsterdam,[62] that MIFARE Ultralight product-based fare cards in the New Jersey and San Francisco transit systems can be manipulated using an Android application, enabling travelers to reset their card balance and travel for free in a talk entitled "NFC For Free Rides and Rooms (on your phone)".[63] Although not a direct attack on the chip but rather the reloading of an unprotected register on the device, it allows hackers to replace value and show that the card is valid for use. This can be overcome by having a copy of the register online so that values can be analysed and suspect cards hot-listed. NXP has responded by pointing out that they had introduced the MIFARE Ultralight C in 2008 with 3DES protection and in November 2012 introduced the MIFARE Ultralight EV1[64] with three decrement only counters to foil such reloading attacks.

• Northwest University, South Africa – Student/staff ID, access control, library, student meals, sport applications, payments[129]
• Linkoping university, Sweden – Student/staff ID, access control, library, copy/print, student discount, payments
• London School of Economics – Access control (Unprotected MIFARE Classic 1K)
• New College School in Oxford – Building access.
• Imperial College London – Staff and student ID access card in London, UK.
• Cambridge University[130] – Student/Staff ID and access card, library card, canteen payments in some colleges[131]
• University of Warwick – Staff and student ID card and separate Eating at Warwick stored value card in Coventry, UK.
• Regent's College, London – Staff and student ID access card in London, UK.
• University of New South Wales – Student ID access card.
• The University of Queensland – Staff and student ID, access control, library, copy/print, building access (MIFARE DESFire EV1)[132]
• University of Alberta – Staff OneCard trial currently underway.
• Northumbria University – Student/staff building and printer access.
• City University of Hong Kong – Student/staff building, library, amenities building.
• Hong Kong Institute of Vocational Education – Student ID card, attendance, library, printers and computers access.
• The Chinese University of Hong Kong – Student ID card, attendance, library, printers and door access control
• University of Bayreuth – Student ID card and canteen card for paying.
• University of Ibadan, Nigeria – Student ID card and examination verification and attendance.(Solutions Colony Ltd)
• Bowen University, Iwo, Nigeria – Student ID card and examination verification and attendance.(Solutions Colony Ltd)
• Afe Babalola University, Ado-Ekiti, Nigeria – Student ID card and examination verification and attendance.(Solutions Colony Ltd)
• Achievers University, Owo, Nigeria – Student ID card and examination verification and attendance.(Solutions Colony Ltd)
• Adekunle Ajasin University, Akungba, Ondo State, Nigeria – Student ID card and examination Verification and Attendance.(Solutions Colony Ltd)
• Auchi Polytechnic, Auchi, Nigeria – Student ID card and examination verification and attendance.(Solutions Colony Ltd)
• University College Hospital, Ibadan (UCH), Nigeria – Student ID card and staff attendance.(Solutions Colony Ltd)
• Federal University of Technology, Minna, Niger State (FUTM), Nigeria – Student ID card and Examination Verification and Attendance.(Solutions Colony Ltd)
• Benson Idahosa University, Benin City, Edo State (BIU), Nigeria – Student ID card and Examination Verification and Attendance.(Solutions Colony Ltd)
• Federal University of Technology, Akure, Ondo State (FUTA), Nigeria – Student ID card and Examination Verification and Attendance.(Solutions Colony Ltd)
• Covenant University, Nigeria – Student ID card and Examination Verification and Attendance.(Solutions Colony Ltd)
• Lead City University, Nigeria – Student ID card and Examination Verification and Attendance.(Solutions Colony Ltd)
• Hogeschool-Universiteit Brussel, Belgium – Student ID card, canteen card for paying, library and building access.
• Southampton University – Student ID card, library and building access – MIFARE Classic 4K.
• Delft University of Technology, Netherlands – Student/Staff ID card, staff coffee machines, lockers, printers and building access.
• Eindhoven University of Technology, Netherlands – Student/Staff ID card, staff coffee machines, lockers, printers and building access currently (2016) rolling out DESfire EV1.
• Dresden University of Technology, Germany – Building access, canteen card for payment
• Chemnitz University of Technology, Germany – Student ID card
• Leipzig University, Germany – Student ID card, canteen card for payment
• Freiberg University of Mining and Technology, Germany – Student/Stuff ID card, building access, canteen card for payment
• University of Jena, Germany – Student/Staff ID card, building access, canteen card for payment
• University of Würzburg, Germany – Student/Staff ID card, building access, library access and fee payment, canteen card for payment
• Technical University of Denmark, Denmark – Student ID card, building access
• University of Duisburg-Essen, Germany – Student/Staff ID card, library access, canteen card for payment
• Walt Disney World Resort – used for tickets, Disney Dining Plan, and room key access
• University of Northampton – Car park access, building access – MIFARE Classic 1K.
• Assumption University (Thailand), Thailand – Student/Staff ID card, library and computers access, canteen, transportation and parking payment, election verification – MIFARE Classic 4K
• Claude Bernard University Lyon 1 Student ID, access control, library (MIFARE 1K)
• University of Strasbourg Student ID, access control (MIFARE 1K)
• Aberystwyth University Student/staff ID, access control, library, copy/print, student discount, payments, building access (MIFARE Classic 4K)
• University of Nottingham – Student ID, access control, library, payments, building access (MIFARE Classic 1K)