Security in Mendix has two sides: you want different people to see different parts of your application and you want to prevent unauthorized access. Both of these can be managed from Studio Pro, discussions around the topic right here in this Space!
Configuring Security roles other than admin role
Replace create/delete with auto-generated microflows and deprecate allow/delete rights
How to give users different rights in different modules?
Grantable roles for multitenant
Why does User Management properties affect my read access?
Email Connector module's setup and configurations
How to decrypt an encrypted password in Mendix app set to bcrypt?
Ability to place a security.txt file
Virus Scan uploaded files using virus total api
Update in HTTP Response Headers - Cache-Control:no-cache to Cache-Control:no-store
Encrypted already stored data in database and change it by the encrypted one
REST API token authentication
How can I set hidden information between users?
Custom Login functionality
How to get the SAML OAuth token
SAML and managing AD groups
XSUAA - Login redirects to a blank page with error 560
In-session authentication EntraID/AzureAD
How to secure forms from bots?