COMMAND
aps (AUTH_PASSWORD)
SYSTEMS AFFECTED
Win NT
PROBLEM
Vincent Lok found following. With basic authentication on IIS,
one can obtain password of users accessing the ASP page via the
server variable AUTH_PASSWORD. The line
<%= Request.ServerVariables("AUTH_PASSWORD") %>
in an asp file will do the trick. With this, web page
authors/content providers (probably not the same person who
administers the web server and NT domain) can easily trap password
of other domain users.
SOLUTION
Basic authentication is never secure as it is possible to capture
password by sniffing and decoding the authentication packets, but
this would require accessibility to the network and some (though
not much) technical expertise. Note that IIS comes by default
with basic auth disabled - you have to be allowed to admin the
site to change this. In IIS 3.0, authentication was set at the
web server level. In IIS 4.0, you can set authentication at the
web site, directory, or file level. SSL secures the transmission
of user name/password pairs over the wire, but a web developer can
still read the AUTH_PASSWORD server variable once the request
hits the server.