    public static function mb_strrpos($haystack, $needle, $offset = 0, $encoding = null)
    {
        $encoding = self::getEncoding($encoding);

        if ($offset != (int) $offset) {
            $offset = 0;
        } elseif ($offset = (int) $offset) {
            if ($offset < 0) {
                $haystack = self::mb_substr($haystack, 0, $offset, $encoding);
                $offset = 0;
            } else {
                $haystack = self::mb_substr($haystack, $offset, 2147483647, $encoding);
            }
        }

        $pos = iconv_strrpos($haystack, $needle, $encoding);

        return false !== $pos ? $offset + $pos : false;
    }
The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.