Hi, make sure you always know where your keys are - someone might steal them or copy them to get into your house. if the keys are missing, have someeone guard the house and replace the lock as soon as possible,
the same is true fo private keys on smartcards. it take more time, knowledge and equipment to get the data from the smartcard, but it's not impossible. the real advantage as david pointed out: with a smartcard you can use keys instead of passwords. passwords are very easy to attack (dictionaries etc.) and the strength of smartcards is, they allow you to not use passwords only. so, in the smartcard+private key scenario there is not much new. the smartcard has a key, so watch it. the new article by anderson and ?? might be a bigger problem for the pay tv industry. but as we all know: they are doing obscurity, playing hide and seek with their foes. personaly i care most about passive attacks. once faked or modified terminals can get the content of the card without me noticing, it will be harder. anyone knows some papers on this? but then again, security can be build with several layers, if necessary. first, trusted and guarded terminals. second, card <-> terminal authentication third, a pin for the cards secret data such as a private key fourth, an additional password for the resource that you want to access, to be used only in combination with the secret key, and only after the key authentication was successfull. but bribes and untrained personal can get around any technical defence such as described. so better get a good insurance, if applicable. regards, andreas David Corco >Hi, > >There have been a few articles about smartcard attacks recently. I would >like to pose a few points in regard to. > >1) These attacks all require physical access to the card. They cannot be > done remotely. >2) These attacks assume the user has not realizes they have lost their > card and has therefore not notified their helpdesk to have the card > revolked. >3) These attacks require the user to very carefully remove layers from the > outside of the chip to expose the card. This is not easy - in most > cases the chip is ruined. >4) These are trial and error attacks - by changing the values of data > stored in eeprom, the attacker hopes to change the behavior of the card > and have it malfunction by returning data the attacker wants to know. > Consider this like a game of minesweeper. You have 262,144 bits in 32k > The majority of those bits being changed will deem the card useless. > In the other cases, unuseful data might be returned. Even if the data > was unciphered in the eeprom (not likely), the user must know where to > look for the data which in most cases isn't linear. >5) These attacks are well known - changing the power, clock to get the > card to malfunction. Heat, Cold, whatever - most do not work and the > attacker has to know alot about the card and data on it. If I wanted > to put this work to get free GSM service why not steal a credit card > and buy a phone card - at least this is less trackable.... > >There are some clear things left out of the article. First, those parts >are not $30 - I believe you would need some chemicals to expose the chip, >you would need a quality microcope, and I'm sure I couldn't pay the >Russian bomb specialist $30 to do this attack for me. > >Point being that there is no perfect solution. I can buy a $10 safe from >Walmart to protect my documents from fire up to 10 minutes at 1900 >degrees, or I could buy a safe from Diebold for $30,000 which survives a >couple of hours at that temperature. The confort of the smartcard is that >I know it is 100% safe as long as it is in my pocket ..... > >Discussion ??? > >Dave > >*************************************************************** >Unix Smart Card Developers - M.U.S.C.L.E. >(Movement for the Use of Smart Cards in a Linux Environment) >http://www.linuxnet.com/ >To unsubscribe send an email to [EMAIL PROTECTED] with >unsubscribe sclinux >*************************************************************** > *************************************************************** Unix Smart Card Developers - M.U.S.C.L.E. (Movement for the Use of Smart Cards in a Linux Environment) http://www.linuxnet.com/ To unsubscribe send an email to [EMAIL PROTECTED] with unsubscribe sclinux ***************************************************************
