The popen API function in TSRM/tsrm_win32.c in PHP before 5.2.11 and 5.3.x before 5.3.1, when running on certain Windows operating systems, allows context-dependent attackers to cause a denial of service (crash) via a crafted (1) “e” or (2) “er” string in the second argument (aka mode), possibly related to the _fdopen function in the Microsoft C runtime library. NOTE: this might not cross privilege boundaries except in rare cases in which the mode argument is accessible to an attacker outside of an application that uses the popen function.
bugs.php.net/bug.php?id=44683
news.php.net/php.announce/79
svn.php.net/viewvc?view=revision&revision=287779
www.openwall.com/lists/oss-security/2009/09/20/1
www.openwall.com/lists/oss-security/2009/11/20/2
www.openwall.com/lists/oss-security/2009/11/20/3
www.osvdb.org/58188
www.php.net/ChangeLog-5.php
www.php.net/ChangeLog-5.php#5.2.11
www.php.net/releases/5_2_11.php
www.php.net/releases/5_3_1.php