mod_cgi/7066: PATH_INFO containing %2F causes server to interpret PATH_INFO as part of file path.

[James Marshall <ja...@jmarshall.com>]

>Number:         7066
>Category:       mod_cgi
>Synopsis:       PATH_INFO containing %2F causes server to interpret PATH_INFO as part of file path.
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sun Jan 14 13:50:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     james@jmarshall.com
>Release:        1.3.15-dev
>Organization:
apache
>Environment:
It's actually on www.apache.org; printenv.cgi shows it.
>Description:
Compare

http://www.apache.org/printenv.cgi/path/info
http://www.apache.org/printenv.cgi/path%2Finfo

These should both call printenv.cgi, right?  The second case results in
"file not found", apparently because the server is looking for the file
/printenv.cgi/path/info .

Related to this, PATH_INFO is being un-URL-encoded before being passed to the
script, e.g.

http://www.apache.org/printenv.cgi/path%20info

results in PATH_INFO of "/path info".  Shouldn't it be passed along without
decoding it, i.e. "/path%20info"?  Otherwise, how could a script distinguish
between PATH_INFOs of "/path%2Finfo" and "/path/info"?  Or are such pairs
always semantically equivalent?

Sticky question and a can of worms, I know.  When are parts of the URL
encoded and when aren't they, etc.  The latest CGI draft seems to imply
that PATH_INFO treatment may vary by server (section 6.1.6), but this
results in non-portable scripts.  Granted, the CGI draft is a BCP.
>How-To-Repeat:
Try http://www.apache.org/printenv.cgi/path%2Finfo
>Fix:
What seems to be lacking is a clear definition of when things are encoded and 
when they aren't.  I know that's very tricky to come up with.  Yes, I've lost
sleep trying to figure this one out.
>Release-Note:
>Audit-Trail:
>Unformatted:
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