Improper Character Handling In PHP Based Scripts like PhpBB, IPB etc.

[h4cky0u <h4cky0u.org () gmail com>]

Well this was after i found somebody posing as me on my site -->
http://www.h4cky0u.org which was actually quite interesting and dangerous
(looking from the social engineering point of view).

Download the following file -

http://www.h4cky0u.org/poc.txt

Make sure you download it and not view it from the browser.  Once you
download that file open it in your text editor. You should see something
like-

--desiredusername
Copy that whole string and try and post it on any PHP Based blog, forum etc
or register a username with that string. Now what do you see? The -- part
from --desiredusername is gone! But apparently its still there. It still
hides within that string(Try and reverse the process you just did). Ok so
the bug has been confirmed. Now come the questions -

1) Is this really a bug in PHP (tested with PHP 4.3.11 and later versions
might as well be affected)? Or am i overlooking something?

2) What is the ASCII code of that -- part in the file if it isn't just 2
simple hyphens? (Tried all the possible methods but couldnt come up with
anything positive.)

3) What are the possible ways to avoid something like this?

--
http://www.h4cky0u.org
(In)Security at its best...

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