[Phplib-users] Two passwords for Challenge_Crypt_Auth
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From: Virilo T. <vi...@su...> - 2003-07-27 11:08:05
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I've readed README.md5_passwords where idicates a vulnerability:=20 "When you change your password, the MD5-hash of your PW is transmitted down the wire. An enterprising cracker could manage to fake a login form and supply the page with the MD5-hashed password, which would then authenticate them. " In the same way, i think that md5 crypt storage isnt a good system when the user password is md5 crypted in client side. The cracker who has = readed database passwords has the same possibilites than with clearly text = storage without the necessity of "break" md5 hash. He only have to manage the = fake=20 login form as in the readme example using directly pasword hash. Im thinking in use two passwords for authentication. One using = Challenge_Auth with clear storage, and other using md5 storage but clear send in the = form. The second password will be crypted in server side before comparison. Thus both attacks will be necessary: database read for the first = password and=20 sniffering for the second. Observe that sniffering the register form send or a password change will = get the first password (if we allow it) and a second sniffering during = authentication could get the second. If its correct, i'll use it for admins authentication. I think its so = hard for customers whose usually one password is enough. If somebody wants see the code, i could post it. Readme file also say: " If you need security you should consider running SSL or no webserver = at all. I looked into public-key encrypting the form response when changing passwords..." I'm interested in SSL authentication examples or pk encryption. Using = phplib or php only (i'm newbye at php too). Thanks, Virilo Tejedor. Email: vi...@su... |