session.c in the session extension in PHP before 5.2.13, and 5.3.1, does not properly interpret ; (semicolon) characters in the argument to the session_save_path function, which allows context-dependent attackers to bypass open_basedir and safe_mode restrictions via an argument that contains multiple ; characters in conjunction with a .. (dot dot).
http://secunia.com/advisories/38708
http://securityreason.com/achievement_securityalert/82
http://securityreason.com/securityalert/7008
http://securitytracker.com/id?1023661
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_2/ext/session/session.c?r1=293036&r2=294272
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_2/ext/session/session.c?view=log
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_3/ext/session/session.c?r1=293036&r2=294272
http://svn.php.net/viewvc/php/php-src/branches/PHP_5_3/ext/session/session.c?view=log
http://www.php.net/ChangeLog-5.php
Published: 2010-03-26
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N
Severity: Medium