source: http://www.securityfocus.com/bid/17439/info
 
PHP is prone to multiple 'safe_mode' and 'open_basedir' restriction-bypass vulnerabilities. Successful exploits could allow an attacker to access sensitive information or to write files in unauthorized locations.
 
These vulnerabilities would be an issue in shared-hosting configurations where multiple users can create and execute arbitrary PHP script code, when the 'safe_mode' and 'open_basedir' restrictions are expected to isolate the users from each other.
 
These issues are reported to affect PHP versions 4.4.2 and 5.1.2; other versions may also be vulnerable.

copy("compress.zlib:///etc/passwd", "/home/<username>/passwd.txt");