What is an incorrect description of the security group application scenario?

A security group in cloud computing is typically used to define the set of permissions for network access to and from virtual machines. When it comes to application scenarios for security groups, they primarily focus on controlling network traffic rather than file system permissions.

The correct scenario would be the ability of a security group to allow or deny specific types of traffic to the virtual machine, such as enabling remote login from certain IP addresses, providing protection against unauthorized access, or restricting access to specific services like FTP.

In contrast, controlling permissions on folders within the virtual machine is more related to the operating system's file system access control mechanisms rather than the network-level controls that security groups provide. Therefore, the description referring to folder permissions does not accurately reflect the primary function or application scenario of security groups in a cloud computing environment.