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212

Because the cards contain a chip which are powered by a coil. The coil is not really a antenna, but half of a transformer. Think your regular mobile charger. This contains a transformer, that will transform the voltage from 230V or 120V AC to 5V DC. This is done by having a coil magnetize some iron, and this iron magnetizes the "receiving coil". If you draw ...


57

Many NFC enabled smartphones can write to these cards with an app like MifareClassicTool. However I've found several phones seem to be able to do it when in reality trying to write to Sector-0 bricks the card. It may be worth testing one or two cards and if it doesn't work buy a dedicated USB writer. First of all a huge number of Mifare Classic Systems only ...


50

NFC (Near Field Communications) cards are not passive. NFC readers constantly transmit RF (radio frequency) energy; this is called a carrier signal. Very close to the reader (within about one wavelength, putting the "Near" in Near Field Communications,) the RF transmission is strong enough to induce enough energy into the receiving antenna to power the ...


46

That depends on what type of tag you use and what level of protection against cloning you want. NFC tags (as defined by the NFC Forum) have no protection against cloning. Such tags are intended as containers for freely readable data (so called NDEF messages). Anyone could read an NDEF message from one tag and duplicate it to another tag. Many NFC tags also ...


24

I have recently cloned a Mifare Classic tag. The scan you have there indicates there is no information stored on your tags, apart from in the first sector. This isn't readable by that app because it does not use the default key. I suggest you first try it with Mifare Classic Tool first, using the extended keys file. There are some common keys there but your ...


20

How can RFID/NFC tags not be cloned when they are passive technology? Your question assumes 2 things: That RFID tags cannot be cloned And they are passive, not active. Both points are incorrect: RFID tags can be cloned. Tags which do not make use of password-protection or over-the-air (OTA) encryption can have their data banks copied into new tags. ...


16

If it is Mifare Classic, that should really not be hard. The general attack on Mifare's broken cryptosystem has been around since 2007. Have a look at this if you want: BlackHat Talk Slides This is indeed most likely easily possible. There are plenty of tutorials about this. Just remember: if your ID/whatever is not stored in the data section but only in ...


13

Is RFID a superset of NFC? (or vice versa?) To quote from the the Wikipedia article "NFC standards cover communications protocols and data exchange formats, and are based on existing radio-frequency identification (RFID) standards..." So RFID is just a name for devices that use radio frequencies to communicate and NFC is one of these. Is all RFID / NFC ...


11

If it is a basic data providing tag, then it can be cloned. If it is a secure tag, it is far more difficult. For secure cards used for payments and authentication, a private key is loaded on to the card and the card never discloses it. The public key is kept by the bank or whoever needs to be able to verify that the card was used. If, for example, the ...


11

Can an attacker get information off the card? Yes, at least some can, and the UK consumer group Which? mentioned in the question did it: Our researchers tested 10 cards (six debit and four credit, from volunteers) to assess security risks. Contactless cards are coded to 'mask' personal data, but using an easily obtainable reader and free software to decode ...


10

There is nothing to stop the NFC being read from a card in the UK according to this study conducted recently by a security firm called ViaForensics. On a NFC enabled phone the article states that the NFC hardware is switched off when the screen is not lit. original link (broken as of 2015-oct-27)


10

If your debit card has an NFC chip on it (the "tap to pay"), it's possible. This presentation discusses two methods. One is skimming an NFC card and using the recovered data for making Card Not Present transactions online. The other is called a "pre-play" attack, where "future transactions" are skimmed from the card in your pocket, and used to make ...


9

Like bluetooth and 802.11, I think we will see eavesdropping used in many attacks. I suspect that some variant of the classic man-in-the-middle attack will crop up too, despite being mitigated as much as possible in the design of the specifications. Although I don't have practical experience or familiarity with these attacks, I can point you to a few ...


9

Information in passports is protected by the Basic Access Control protocol, the standard can be found here. In order to read from the passport you need certain pieces of information; the passport number, the D.O.B and the date of expiry. NFC TagInfo is quite a nice app that can read passports amongst other things, make sure you enter the correct information ...


9

First and foremost: if you want security, don't use MIFARE cards. They aren't the best at security. Even if a card isn't vulnerable to something like a hardnested attack or a brute-force attack, the card's data can still be sniffed over-the-air (which will include the keys or allow keys and data to be easily recovered). Generally, most "secure" ...


8

NFC devices which do not use either public key crypto, encrypted tokens or HMAC tokens or similar cryptographic mechanisms where there is a secret that never leaves the device, they can all be impersonated. Simple devices often just have a static string of data which they broadcast. Many newer NFC devices as well as most enterprise grade devices since ...


8

It is about risks weighted against benefits. Requiring PIN for NFC transactions would reduce main NFC advantage - speed. NFC payments without PIN are used only for payments of limited amount and usually for limited number of transaction and/or limited total amount of transactions per day. Maybe also other bank specific rules apply; at least I was informed ...


8

The card is supposed to authenticate the reader, so that only legitimate (bank-issued) readers can access the card. This does not preclude a legitimate reader making fake payments, either because the merchant is dishonest or because the reader was stolen. The payment should be traceable though, and the bank should be responsible for any charge resulting of ...


7

You can check this paper : http://media.blackhat.com/bh-us-12/Briefings/C_Miller/BH_US_12_Miller_NFC_attack_surface_WP.pdf It's from a talk given by Charlie Miller at BlackHat 2012 : Near Field Communication (NFC) has been used in mobile devices in some countries for a while and is now emerging on devices in use in the United States. This technology ...


7

No, contactless transactions are not more secure than contact transactions. The whole contactless business has a lot more to do with making payments easier on the point of sale (and possibly enable future developments of the smartcard business) than in increasing security. Ridiculous early US implementations aside, we have a couple things going on here: ...


6

Some issues with contactless payments and digital wallets: Loss or theft -- an attacker gaining access to a device could allow access to the confidential information and allow continuous fraudulent transactions until accounts were disabled and/or fraud was caught. Pulling a SIM card could prevent even the most-stalwart lock and/or lockdown protections, and ...


6

Are you wondering if such technology exist, or are you wondering if the speech of a company you know but for some reason do not mention is realistic from a technical point of view? No matter what, such company exist, an example would be Amourcard. I do not know if there are other, they claim to be the first to offer such service. This company targets more ...


6

I'll try to make it rather short and try to answer every question. How is this possible without power? There is power like usual. It works by the same electromagnetical principle as a transformer (which is contactless as well). Or like one of those modern(ish) contactless smartphone chargers where you just lay your phone on a plate instead of plugging it ...


5

NFC is just another medium like wires, wifi, microwave, light-comms, etc. It will be incumbent on the security professionals to create and guide their safe use whether it is for payments, data sharing or any other purpose. Being an invisible medium probably brings its own risks in terms of awareness, but there is nothing intrinsic beyond its invisibility ...


5

Edited: OK. As there is request for "short answer" here is "executive summary" here it is: Question: “So all the reading devices must know the secret key, too. But there can be many readers from many vendors (e.g. coffee machines, small USB readers at cash registers, access control panels…), do all of them really have the secret key? Is there a standard on ...


5

You would need to extract the key of the card, which is what these cards generally protect against. Authentication protocols in general depend on a challenge response. In case of Mifare EV1 this is done with AES or 3DES. Basically the nonce (incase of DESfire 2 nonces) are encrypted: Reader sends b1,b2 Card replies 3DES(b1) Card replies 3DES(b2) Reader ...


5

I've actually tried a similar thing at my old school, and after months of research, this is what I found: Write to sector 0 and hope for the best, maybe it's just the ID that's important. MFCUK, never got around to trying it myself, but if I recall correctly, it will use the security flaw of the classic and figure out the key. Brute force, the Mifare ...


4

To identify a card, you power it using a carrier wave on its frequency and wait for answers. If there is no answer, you switch to a different frequency and protocol and so on until you get communication from the card (you may need to use multiple readers as different frequencies require different readers). Using your phone is accurate, I mean, if the phone ...


4

My understanding of NFC is that, as a standard, it doesn't offer any provision for encryption of data security. This means you'll have to implement security on top of it. So first: the important part: do not try to implement it yourself: You do not have the understanding necessary to design it properly (as demonstrated by your question) Even with proper ...


4

To answer the question of copying/emulation yes it is possible but there are multiple standards for NFC transactions. There was research at blackhat that was presented that demonstrated credit card emulation but it required two devices, and one device had to be running a specific version of CyanogenMod that introduced the changes which allowed for skimming ...


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