The ip2long function in PHP 5.1.4 and earlier may incorrectly validate an arbitrary string and return a valid network IP address, which allows remote attackers to obtain network information and facilitate other attacks, as demonstrated using SQL injection in the X-FORWARDED-FOR Header in index.php in MiniBB 2.0.  NOTE: it could be argued that the ip2long behavior represents a risk for security-relevant issues in a way that is similar to strcpy's role in buffer overflows, in which case this would be a class of implementation bugs that would require separate CVE items for each PHP application that uses ip2long in a security-relevant manner.