In message <[EMAIL PROTECTED]>, Ian Grigg writes: >> >> Don't be silly. It's not a threat because people generally use >> SSL. Back in the old days, password capture was a very serious >> threat. It went away with SSH. It seems to me quite likely that >> it would be a problem with web browsing in the absence of SSL. > > >Right... It's easy to claim that "it went away" >because we protected against it. Unfortunately, >that's just a claim - there is no evidence of >that. > >This is why I ask whether there has been any >evidence of MITMs, and listening attacks. We >know for example that there were password >sniffing attacks back in the old days, by >hackers. Hence SSH. Costs -> Solution. > >But, there is precious little to suggest that >credit cards would be sniffed - I've heard one >isolated and unconfirmable case. And, there is >similar levels of MITM evidence - anecdotes and >some experiences in other fields, as reported >here on this list. >
I think that Eric is 100% correct here: it doesn't happen because it's a low-probability attack, because most sites do use SSL. I think that people are forgetting just how serious the password capture attacks were in 1993-94. The eavesdropping machines were on backbones of major ISPs; a *lot* of passwords were captured. Furthermore, the technology has improved -- have you looked at dsniff lately, with the ARP-based active attack capability? And credit cards are much easier to grab -- they're probably sent in one packet, instead of several, and the number is a self-checking string of digits. It's also worth remembering that an SSL-like solution -- cryptographically protecting the transmission of credit card number, instead of digitally signing a funds transfer authorization linked to some account -- was more or less the only thing possible at the time. The Internet as a medium of commerce was too new for the banks to have developed something SET-like, and there wasn't an overwhelmingly-dominant client platform at the time for which custom software could be developed. (Remember that Windows 95 was the first version with an integral TCP/IP stack.) *All* that Netscape could deploy was something that lived in just the browser and Web server. SET itself failed because the incentives were never there -- consumers didn't perceive any benefit to installing funky software, and merchants weren't given much incentive to encourage it. --Steve Bellovin, http://www.research.att.com/~smb --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]