MySQL 取消免密登陆失败

Question

MySQL8.0设置密码后，仍然可以免密登陆

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> exit
Bye
[root@bogon mysql]# 
[root@bogon mysql]# 
[root@bogon mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 14
Server version: 8.0.31-commercial MySQL  Server - Commercial

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 
mysql> 
mysql> select user,host,authentication_string from mysql.user ;
+------------------+-----------+------------------------------------------------------------------------+
| user             | host      | authentication_string                                                  |
+------------------+-----------+------------------------------------------------------------------------+
| mysql.infoschema | localhost | $A$005$THISISATANDPASSWORDTHATMUSTNEVERBRBEUSED |
| mysql.session    | localhost | $A$005$THISISACOLTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| mysql.sys        | localhost | $A$005$THISISACOMBINTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| root             | localhost | $A$005$YS&{@VTMi8|mAXhxfxDk/seIDuFPtc66RqTN/ |
+------------------+-----------+------------------------------------------------------------------------+
4 rows in set (0.00 sec)

mysql> exit

操作系统：centos7 、MySQL版本：8.0.31

为什么设置了MySQL密码，还能免密登陆呢？

Answer 1

我擦，居然是我的密码有bug。。。

1.设置密码为“Newpassword”，一切正常，没有密码不能登陆。

mysql> 
mysql> alter user user() identified by 'Newpassword';
Query OK, 0 rows affected (0.03 sec)

mysql> 
mysql> exit
Bye
[root@bogon mysql]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
[root@bogon mysql]# mysql -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 40
Server version: 8.0.31-commercial MySQL Server - Commercial

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 

2.修改密码为我想设置的密码，问题就又出现了，空密码或者我设置的密码都可以正常登陆。

mysql> 
mysql> alter user user() identified by 'xxxxx';
Query OK, 0 rows affected (0.02 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> exit
Bye
[root@bogon mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 41
Server version: 8.0.31-commercial MySQL Server - Commercial

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> exit
Bye
[root@bogon mysql]# mysql -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 42
Server version: 8.0.31-commercial MySQL Server - Commercial

Copyright (c) 2000, 2022, Oracle and/or its affiliates.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 

目前只试出来我自己的密码会出现这个问题。。。。