3 ms·

When someone at my office spotted this story earlier in the day, a bunch of us quickly ran around playing with an android app (which doesn't have permissions to

by ifni 13y ago

When someone at my office spotted this story earlier in the day, a bunch of us quickly ran around playing with an android app (which doesn't have permissions to phone home and censors out some of the data) to see what info we could pull off our cards. https://play.google.com/store/apps/details?id=com.samj.CardTest https://play.google.com/store/apps/details?id=com.samj.CardT... Name, number, and expiry are readily available. We figured you could probably replay that data to get some free gas with stolen credentials... but the scanning range with phones is more akin to "hold the card up against it for several seconds to read" than "walk through a crowded room".

vy8vWJlco 13y ago
That is probably a moderately-variable function of the power output and sensitivity/gain of the radio in the phone (and card) used. (A crowded subway in Japan would probably be ideal conditions. :p) Other phones may have noticeably better range, or range might be increased by simply going out of spec using lower level RF controls (if lower level access is possible per-controller, since as I don't see anything about power control in the Android docs). http://android.stackexchange.com/questions/5044/nfc-functionality-in-google-nexus-s http://android.stackexchange.com/questions/5044/nfc-function... https://developer.android.com/guide/topics/connectivity/nfc/index.html https://developer.android.com/guide/topics/connectivity/nfc/...
- jrockway 13y ago
  A high-gain antenna at the NFC frequency (13.56MHz) would be about 11 meters wide and 6 meters long. This is probably why there isn't much long-distance NFC skimming going on. (If you're an ARRL member, there's a good article on building a 14MHz directional antenna at http://www.arrl.org/files/file/protected/Group/Members/Technology/tis/info/pdf/0107028.pdf http://www.arrl.org/files/file/protected/Group/Members/Techn.... It's big, and one resonant at 13.56MHz would be a little bit bigger. But it is something that's physically possible and would make for an interesting experiment.) Edit: Here's another idea (and the article is free): http://www.arrl.org/files/file/protected/Group/Members/Technology/tis/info/pdf/5501022.pdf http://www.arrl.org/files/file/protected/Group/Members/Techn...
  - vy8vWJlco 13y ago
    Easily concealable in a floor or wall. :) (I jest.)

by ifni 13y ago

vy8vWJlco 13y ago

That is probably a moderately-variable function of the power output and sensitivity/gain of the radio in the phone (and card) used. (A crowded subway in Japan would probably be ideal conditions. :p) Other phones may have noticeably better range, or range might be increased by simply going out of spec using lower level RF controls (if lower level access is possible per-controller, since as I don't see anything about power control in the Android docs). http://android.stackexchange.com/questions/5044/nfc-functionality-in-google-nexus-s http://android.stackexchange.com/questions/5044/nfc-function... https://developer.android.com/guide/topics/connectivity/nfc/index.html https://developer.android.com/guide/topics/connectivity/nfc/...

jrockway 13y ago
A high-gain antenna at the NFC frequency (13.56MHz) would be about 11 meters wide and 6 meters long. This is probably why there isn't much long-distance NFC skimming going on. (If you're an ARRL member, there's a good article on building a 14MHz directional antenna at http://www.arrl.org/files/file/protected/Group/Members/Technology/tis/info/pdf/0107028.pdf http://www.arrl.org/files/file/protected/Group/Members/Techn.... It's big, and one resonant at 13.56MHz would be a little bit bigger. But it is something that's physically possible and would make for an interesting experiment.) Edit: Here's another idea (and the article is free): http://www.arrl.org/files/file/protected/Group/Members/Technology/tis/info/pdf/5501022.pdf http://www.arrl.org/files/file/protected/Group/Members/Techn...
- vy8vWJlco 13y ago
  Easily concealable in a floor or wall. :) (I jest.)