Defeating Virtual Keyboards and Phishing Banks

An anonymous reader writes "Noam Rathaus writes on the SecuriTeam Blogs how most Image Click-Me virtual keyboards schemes used by banks to fight phishing trojan horses can be easily broken, even (and especially) when encryption is used. He then discusses how screenshots of the pointer location are over-kill, and describes how to kick these security measures out of the way." From the article: "Instead of sending the remote image and waiting for the key-stroke information to be sent back to the server (the technique which the screenshots for pointer location on-click described above was used) some banks send the PIN number in cleartext, while others encrypt them, one such example is cajamurcia. Even when the encryption is used, banks tend to implement it badly making it easy to recover the PIN number from the encrypted form. I investigated a bit more on how cajamurcia handles such PIN strokes (with virtual keyboards) and I noticed something strange, they take the timestamp of their server (cajamurcia) and send it to you - this already posses a security problem - and this timestamp is then used to encrypt the PIN number you entered"

Comments

No Surprise

[daeg]

This is no surprise at all. Keyloggers will be a thing of the past soon enough for the major hackers.

More scary is the fact that adding a simple network device will allow a virus to log all Internet traffic. Look at HTTPLook (a small app used to sniff HTTP traffic). It comes with a small HTTPS module that intercepts HTTP traffic transmitted via HTTPS.

Using such a device will also help cut down on the amount of data hackers can get -- HTTP traffic is useless to them. Why do they care you went to Google and searched for "hot gay wrestlers"? They don't. HTTPS, on the other hand, will set off alarm bells -- if a server is worried enough about security that it pays for certificates, the data must be worth something, right?

The solution is that logging into secure systems needs to require a physical presence. An older system I maintained a few years ago for the Mortgage industry used a username, password, and a key from a small business card in their wallet. Each month users received a new card, and each card had about 50 numbers on it. The system knew which numbers each user had and only allowed each number to be used once. Logging in with a wrong number would flag your account, repeated attempts would lock it. Yes, it increased support load when someone lost their card (the cards were unmarked so if someone found it, the numbers are useless), but it was fairly secure and generally a lower cost alternative to biometrics (and much more portable).

This combines the "something you know" authentication scheme (username, password) and the "something you have" scheme (password card). The third type is "something you are" -- biometrics.

(Failure point: person gets kidnapped. If a user gets kidnapped, security is the least of the worries until they are recovered. Failure point: if the database with the numbers is compromised, the system is no longer secure. If the database is compromised, they no longer need to log in, and no secret numbers will stop them.)

Re:dumb

[theCoder]

If you use a smartcard, the crypto happens on the card itself. The private key never leaves the card. Simply speaking, a request is made to the card to sign something, and it gives back the signature. This means that no one listening on the computer can duplicate the authentication (assuming there is nothing else wrong with the protocol, such as replay attacks, any sort of man in the middle, etc).

In essence, the smartcard idea is assuming that your machine could be compromised, and is moving the authentication to another machine (the smartcard) which is much harder to compromise.