Binary Logging Security: Balancing Functionality and Risk in MySQL/MariaDB

• Binary logging is a feature that records all changes made to a database in a binary format. This log can be used for various purposes, including:
  • Replication: Keeping multiple servers (slaves) synchronized with a master server.
  • Point-in-Time Recovery: Restoring the database to a specific point in time based on the binary logs.

Security Concerns with SUPER Privileges and Binary Logging

• The SUPER privilege grants a user extensive control over the MySQL server, including the ability to:

  • Create, alter, or drop any database or table.
  • Grant or revoke privileges to other users.
  • Shut down the server.

Mitigating the Risk: SUPER vs. CREATE ROUTINE

• To address this security concern, MySQL and MariaDB restrict the ability to create stored functions, procedures, and triggers (collectively called "routines") when binary logging is on and the user doesn't have SUPER privileges. This prevents unauthorized users from introducing potentially harmful code into the database.
• Users who need to create routines typically have the CREATE ROUTINE privilege. This privilege allows them to create routines within their own schemas, but it doesn't grant the ability to perform actions that require SUPER privileges (like modifying system tables).

Resolving the "SUPER privilege" Error

• If you encounter an error indicating you lack SUPER privileges when creating routines with binary logging enabled, there are a few solutions:

# Enable binary logging (default is off)
log_bin = /path/to/binary-log

# Optional: Trust routine creators (less secure)
# Not recommended for production environments
log_bin_trust_function_creators = 1

User Privileges (using GRANT statement):

GRANT CREATE ROUTINE ON my_database.* TO my_user;  # Allows routine creation in my_database

# Grant SUPER privileges with caution (increases security risk)
GRANT SUPER ON *.* TO my_user;

Error Message (Example):

ERROR 1227 (Access Denied) You do not have the SUPER privilege and binary logging is enabled

Remember:

• Modifying these settings directly in configuration files or using the mysqld command is typically done by administrators.
• Granting SUPER privileges should be done with extreme caution due to the high level of access it provides.
• Disabling binary logging is generally not recommended as it removes the benefits of replication and point-in-time recovery.

• This is the most secure and recommended approach. Grant the CREATE ROUTINE privilege to the user who needs to create routines. This allows them to create routines within their assigned schemas without compromising the security of the entire system.

User Procedures:

• If the desired functionality can be achieved using user procedures (functions or stored procedures that don't rely on triggers), users with CREATE ROUTINE can create them. User procedures don't require SUPER privileges and are a good alternative when triggers aren't strictly necessary.

Scheduled Tasks:

• Consider using external tools like cron jobs or the built-in MySQL scheduler (if enabled) to execute tasks at specific times or intervals. These tools can trigger scripts containing the desired logic, potentially eliminating the need for routines altogether.

Administrative Delegation:

• If specific routines require SUPER privileges, consider creating them as an administrator and granting execute permissions to the appropriate users. This approach separates routine creation (by a trusted administrator) from execution (by designated users).

Stored Functions in Applications:

• If your application logic involves calculations or data manipulation, explore implementing the logic as stored functions within your application code. This approach avoids relying on database routines and doesn't require special privileges.

Choosing the Best Method:

The best alternate method depends on your specific needs and security requirements. Here's a quick guide:

• Routine creation for specific users: CREATE ROUTINE privilege
• Simpler logic without triggers: User procedures
• Scheduled tasks/external logic: Scheduled tasks or application logic
• High-privilege routines (use with caution): Administrative delegation