WebApp Sec mailing list archives
RE: Smart card proposal
From: "Ofer Shezaf" <Ofer.Shezaf () breach com>
Date: Tue, 25 Jan 2005 16:01:07 -0500
I think that Mary Ann provides the most complete overview of the technical aspects of things. One addition is that we should distinguish between processor based devices and memory based devices. Both smartcard and USB tokens can be both processor based and memory based. Only processor based devices can perform public key based challenge response without letting out the private key. Such a mechanism makes duplicating the hardware device very difficult (that is to say impossible for now). As far as I know most smart cards based credit cards are EMV based, a standard developed by Visa, MasterCard and Europay (www.emvco.com) and are processor based. Other smartcards or USB tokens out there may be memory based. But my experience in banking security shows that the issue is probably more business, marketing and security awareness than technology: While USB drives don't require a drive, they don't fit consumer applications as customers are not would be reluctant to carry multiple USB tokens. On the other hand, credit card size smart cards are perfect - but require a drive. Interestingly enough, there where a few attempts to use smart card based authentication for consumer banking. For example American Express have been offering smart card readers for free to use with their Blue Chip cards (https://www124.americanexpress.com/cards/loyalty.do?page=blue.idkeeper) . Did any one of you seleted AmEx for that? Has it? A startup which I met developed a credit card size challenge response authentication that does not require a drive (actually communication with the PC was audio based) without much success. Banks did not buy it. Why these attempts failed? Lack of real security concern by vendors? By consumers? Price of the technology (and the required customer service)? Probably all. Maybe the sharp rise in phishing and related identity theft issues will make consumer and the industry adapt such a solution. Another encouraging fact is that the credit card companies for using smart cards instead of magnetic stripes. ~ Ofer Ofer Shezaf CTO, Breach Security Tel: +972.9.956.0036 ext.212 Cell: +972.54.443.1119 ofers () breach com http://www.breach.com
-----Original Message----- From: maburns () safenet-inc com [mailto:maburns () safenet-inc com] Sent: Tuesday, January 25, 2005 2:27 AM To: hugo.fortier () gmail com; rms () computerbytesman com Cc: webappsec () securityfocus com Subject: RE: Smart card proposal Hugo The USB Key token would eliminate the need for the smartcard reader
and
the pin can be typed on the keyboard since It does not really matter if
the
keystrokes are copied since with two-factor authentication you need
the
combination of the physical device and the pin# ( two factor is - something you have (USB key) with something you know (pin#). The RSA random password generator won't work for the reason below. The
RSA
secure ID are more expense than an USB token like Rainbow iKey and
need a
battery replacement (USB token does not). Plus RSA is a random
password
generator and is not really two factor authentication and the
deployment
on a RSA Radius server is such that all remote users need to be on the
system
since the sever cannot allow some to have the RSA token and others in
the
directory to have user name and passwords. USB tokens can be issued to some users (who want high security) and
the
others can remain on user names and password. Thus providing the bank
with
the answer they need. Use the USB key for top security and be
protected or
continue to use user name and password but at your own risk. If the user loses their key they call the help desk and get a temp
user
name and password and the bank sends out another key same as if they lost
their
ATM card, they get a replacement. Or they can elect to switch over the username and password if they don't like the key. Mary Ann -----Original Message----- From: Hugo Fortier [mailto:hugo.fortier () gmail com] Sent: Monday, January 24, 2005 10:20 AM To: Richard M. Smith Cc: Webappsec List Subject: Re: Smart card proposal USB Flash drive and Credit Card sized CD are't to be compaired with SmardCard. They have none of the propriety that a smartcard have... While it's is somewhat better than storing the key directly on the computer, it should't be considered a lot more secure. And it be a lot cheaper
tu
just use a crypto key stored on the PC. SmartCard readers are getting cheaper and cheaper, only issue is that inexpensive one does not have PIN Pad included in the reader. It's a
bad
idea to enter your pin on your computer keyboard. I agree with you that PIN number generator are interesting, but for a online bank they does't provide the advantage a smart card would give them
(Aka
Digital Signature). Also those RSA Token have short lifetime, due to the fact that they
have
built-in battery and are easy to break. I doubt RSA Token are cost effective on big deployment like Online banking... We have to remember that the cost of the solution have to be lower
than
the lost caused by fraud. Hugo On Mon, 24 Jan 2005 07:27:54 -0500, Richard M. Smith <rms () computerbytesman com> wrote:Since almost no PCs that I am aware of have SmardCard readers, I
don't
see how this scheme works. Could a USB flash drive or a credit card-sized CD ROM be used instead? (See http://www.mediaheaven.co.uk/cd-business-cards.htm) These devices typically don't require new software. I still like a PIN-number generator device for a key ring as the
best
method to improve security beyond passwords and PINS. One of these devices generates random PIN numbers that are only known by the bank and the person who is holding the device. They are popular her in
the
States in remote access systems to corporate networks. (See http://www.rsasecurity.com/node.asp?id=1173). Richard -----Original Message----- From: Rogan Dawes [mailto:discard () dawes za net] Sent: Wednesday, January 19, 2005 5:47 AM To: Webappsec List Subject: Smart card proposal Hi folks, As part of the discussion recently about phishing, I was thinking about how a hardware token (and a smart card in particular) could be used to secure web transactions. It also struck me that more and more banks are issuing credit or
debit
cards with smart-card capabilities. This led to the thought that banks could use the smart-card capabilities (via a smart-card reader) to store a private key and
SSL
client certificate, which would be used to authenticate their
clients
when they wish to perform internet banking. Positive consequences: The bank is performing the same effective authentication as they do
at
their ATM's. Something you have (the card) and something you know
(the
PIN). This may or may not be the same PIN as would be used in an
ATM.
This would be a policy decision, made by the issuing bank. Policy decisions can be enforced on the smart card, because the
smart
card can run applications. So policies such as PIN complexity, lockout, etc can all be specified by the bank, and enforced. This is platform independent, browser independent, CPU independent, etc. Users already have an idea of how to protect their credit cards.
They
know what the implications are if they get lost or stolen. They tend to keep them in a safe place. Even if they do get compromised, the card is still protected by a PIN, and is effectively unusable. ATM's mostly already have infrastructure to read and communicate
with
smart cards. Users can use ATM's as self-service terminals to set up their internet banking. e.g. the user enters their PIN at the ATM, selects Internet Banking, Register. The ATM instructs the smart card to generate a private key, takes a copy of the public key, generates
a
CSR, requests the Bank's CA to sign the cert, and installs the cert into the smart card. It then asks the user to choose a PIN for the certificate, so that it cannot be accessed without it. At the same time, it links the certificate to the same accounts that the user
can
access via the ATM, so that Internet banking is effectively
seamless.
If the user forgets the certificate PIN, and tries to guess it more than ${policy} times, the smart card locks it out. Then, the user
can
go to an ATM, enter his ATM PIN, request a certificate PIN reset,
the
ATM then supplies a (card specific) PIN Unlock Key, which allows the user to enter a new PIN for the cert. The certificate lifetime would be the same as the validity period of the credit card. When the bank issues a new credit card, the user should go back to an ATM, and reregister for Internet banking. Alternatively, if the user is already registered, the bank can pregenerate a key and certificate in the card, register it with Internet Banking, and provide the user with the certificate PIN in
the
same way as they do with the ATM PIN. Depending on the bank's policy, the user may be able to change the
PIN
at their own computer. This would however mean that the bank would
not
be in a position to know what the current certificate PIN actually
is.
An alternative is to require the PUK before allowing PIN changes.
The
PUK could only be provided by the ATM . . . allowing the bank to obtain a copy of the certificate PIN . . . Negative Implications: If the credit card is stolen, there is a risk of access via the Internet as well. This may or may not already be an issue, if users can self-register using their credit card PIN. (possible in some countries) Using the smart card at a merchant might allow the merchant to issue additional internet banking transactions while the card is inserted
in
the slot, and the PIN has been entered into their card processing device. I think the close coincidence of the fraudulent transactions with a legitimate transaction would be suspicious. Note that it
would
(should) not be possible to delay the transaction until after the
card
is taken out. (Question: If I connect using a client cert, establish
a
SSL shared session key, then remove the smart card, can I continue
to
use that session key?) Also, most merchants do not have access to reprogram their card terminals, this is generally done by the
supplier.
Session Riding: One thing that I have ignored up until now is the issue of session riding, where an attacker makes use of the fact that the SSL connection is transparently created. One thing mitigating against that is the requirement for the user to have entered their PIN to access the certificate on the card. It may be possible to set a timeout on the card, so that the PIN must bereenteredto continue transacting. Thoughts? Comments? Rogan -- Rogan Dawes *ALL* messages to discard () dawes za net will be dropped, and added to my blacklist. Please respond to "lists AT dawes DOT za DOT net"
Current thread:
- Re: Smart card proposal, (continued)
- Re: Smart card proposal Rogan Dawes (Jan 24)
- Re: Smart card proposal Rishi Pande (Jan 24)
- Re: Smart card proposal Rogan Dawes (Jan 24)
- Re: Smart card proposal Hugo Fortier (Jan 24)
- Re: Smart card proposal Rogan Dawes (Jan 27)
- Re: Smart card proposal Rogan Dawes (Jan 24)
- Re: Smart card proposal Hugo Fortier (Jan 24)
- RE: Smart card proposal Richard M. Smith (Jan 24)
- Re: Smart card proposal Rogan Dawes (Jan 27)
- RE: Smart card proposal Richard M. Smith (Jan 27)
- Re: Smart card proposal DE Gustafson (Jan 27)
- Re: Smart card proposal Koh Gim Leng (Jan 28)
- RE: Smart card proposal Lyal Collins (Jan 28)
- Security Webcast Series JoeStagner (Feb 02)