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Old, php fileupload overflow vuln - need help.
From: czubakabra <czubakabra () o2 pl>
Date: Sat, 05 Aug 2006 17:45:46 +0200

Hi,
Some time ago, Stefan Esser find potencialy exploitable vulnerability
in PHP upload code (exactly php_mime_split() function). I need to create
exploit code for 4.0.4pl version of PHP, but I think this vulnerability
cannot cause remote code execution.
advisory: http://security.e-matters.de/advisories/012002.html

Vulnerable code:                

                loc2 = memchr(loc + 1, '\n', rem);
                rem -= (loc2 - ptr) + 1;
                ptr = loc2 + 1;

And now:

1. ptr could be 0x1 if loc2==0, crash on next memchr() on state=2 or state=3
2. ptr could be > (cnt + buf) when memchr() find '\n' somewhere in memory,
overwrite one byte: * (loc2 - 1) = '\0';

If anyone exploit this vulnerability? I would be very thankfull if someone can
help me.

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