(1)
Some RFID tags can hold more than 4k bytes of data.
(Philips / NXP Contactless Smartcards)

(2)
Contact cards have CPU and data storage... hence if some one has the Encryption keys... then it is possible to put some virus code on to contact cards and transfer it off on to another PC.

(3)
streching the technology... The newer RFID smart cards already have CPU and data storage. But these cards are for secure transactions like banking and have high levels of Encryption.

(4)
Most RFID is used for data storage/transfer and are write once - read many . AND the storage is 10 to 200 bytes of data typically.

(5) EPC Global 900MHz Taging systems to be used by WallMart etc
have typically 128bits of data. Yes, Bit's data.

(6) All of the RFID cards with CPU have Encryption... the probability of virus is very very small.


While it is theorectically possible - the probability is very very very small and only if the Encryption keys are known.

Some web sites need to gather the "actual facts" a bit better, before presenting them.


ANY CPU system, with enough code memory storage, well defined operating system, no Encryption and minimal protection - it is theorectically possible.


(Can you tell I've been tinkering with this RFID stuff)

Joe