只要有系统root密码就可以破解：

[root@host- ~]# vim /etc/my.cnf　　　　　　　　　　　　　　　//在配置文件中加入如下内容

[mysqld]

skip-grant-tables

[root@host- ~]# systemctl restart mysqld   　　　　　　　　//重启MySQL服务

[root@host- ~]# mysql

mysql> update mysql.user set password=password("Yanglt456.") where user="root" and host="localhost";　　　　//设置密码

mysql> flush privileges;　　　　　　　　　　　　　　　　　　　　　//刷新　　　　　　　　　　　　　　　　　　　　　　　　　　

mysql> \q

[root@host- ~]# vim /etc/my.cnf                          //注释掉下边内容，或者直接删除

[mysqld]

#skip-grant-table

[root@host- ~]#systemctl restart mysqld　　　　　　　　　　 //重启服务

[root@host- ~]# vim /etc/my.cnf

[mysqld]

skip-grant-tables

mysql> select user,host,authentication_string from mysql.user;

+---------------+-----------+-------------------------------------------+

| user          | host      | authentication_string                     |

+---------------+-----------+-------------------------------------------+

| root          | localhost | *8F59EEA84BC6AA6A57ECD4C0377518281DADC1BA |

| mysql.session | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE |

| mysql.sys     | localhost | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE |

+---------------+-----------+-------------------------------------------+

 rows in set (0.01 sec)

mysql> desc mysql.user;

+------------------------+-----------------------------------+------+-----+-----------------------+-------+

| Field                  | Type                              | Null | Key | Default               | Extra |

+------------------------+-----------------------------------+------+-----+-----------------------+-------+

| Host                   | char()                          | NO   | PRI |                       |       |

| User                   | char()                          | NO   | PRI |                       |       |

| authentication_string  | text                              | YES  |     | NULL                  |       |

| password_expired       | enum('N','Y')                     | NO   |     | N                     |       |

| password_last_changed  | timestamp                         | YES  |     | NULL                  |       |

| password_lifetime      | smallint() unsigned              | YES  |     | NULL                  |       |

| account_locked         | enum('N','Y')                     | NO   |     | N                     |       |

+------------------------+-----------------------------------+------+-----+-----------------------+-------+

 rows in set (0.01 sec)

mysql> update mysql.user set authentication_string=password("Yanglt456.") where user="root";

mysql> flush privileges;

mysql> \q

[root@host- ~]# vim /etc/my.cnf

[mysqld]

#skip-grant-tables  //注释掉

[root@host- ~]# systemctl restart mysqld            //重启mysql服务

[root@host- ~]# mysql -p"Yanglt456."                //密码已改变