This package ensures that your application doesn't have installed dependencies with known security vulnerabilities.

~$ composer require roave/security-advisories:dev-master@DEV

This package does not provide any API or usable classes: its only purpose is to prevent installation of software with known and documented security issues. Simply add "roave/security-advisories": "dev-master@DEV" to your composer.json "require" section and you will not be able to harm yourself with software with known security vulnerabilities.

For example, try following:

~$ composer require roave/security-advisories:dev-master@DEV
~$ # following commands will fail:
~$ composer require symfony/symfony:2.5.2
~$ composer require zendframework/zendframework:2.3.1 

This package can only be required in its dev-master@DEV version: there will never be stable/tagged versions because of the nature of the problem being targeted. Security issues are in fact a moving target, and locking your project to a specific tagged version of the package would not make any sense.

This package is therefore only suited for installation in the root of your deployable project.

This package extracts information about existing security issues in various composer projects from the FriendsOfPHP/security-advisories repository.