Application Greylisting

Application Greylisting Software

Visibility is everything. Even with application control, gaining a clear picture of the network is crucial. When overwhelmed by the amount of data they receive, IT administrators often create narrow blacklists and whitelists, applying policies to only frequently used applications. This results in something called a greylist comprised of applications omitted from both, which can open up risks in an organization, as network admins typically have little visibility over greylisted applications.

As new applications get added, managing and securing networks becomes a challenge. The way to avoid this would be to create actionable policies encompassing all discovered applications to gain holistic visibility.

What is application greylisting?

Application greylisting is the process of identifying and listing the applications that are yet to be included in either a whitelist or a blacklist. With regards to application control, all applications that are allowed to run must be whitelisted while the one's that need to be blocked are blacklisted.

Applications that are neither critical to the business nor threaten security are often omitted from whitelists and blacklists, without any policy being applied to them. These applications are called greylisted applications. To gain total control over the applications running in your organization, it's best to keep the number of applications in your greylist at zero.

How do greylisted applications affect productivity and security?

The two obvious approaches to deal with greylisted applications is to either allow them to run or prohibit them from running. Enterprises that are keen on establishing the principle of Zero Trust usually block all greylisted applications in order to have a tight grip over their network. While this helps with security, blocking greylisted applications from running can cause serious chaos for IT teams.

IT administrators will be flooded with access requests every time an inadvertently defined whitelist policy is deployed. Additionally, all new applications installed will also be prohibited from running, as they would directly fall into the application greylist. It's essential to strike the right balance between security and productivity when dealing with greylists.

How does ManageEngine Application Control Plus deal with greylists?

With flexibility modes like Audit Mode and Strict Mode, admins get a preview of how their network would function if they choose to run the applications currently in the greylist. This enables them to make informed decisions before they enforce policies to add greylisted applications to the blacklist.

Identifying and resolving greylisted applications

  • Tentative whitelists can be built and policies associating them with custom groups of users/systems can be deployed using Audit mode. This mode allows both whitelisted and greylisted applications to run smoothly with simultaneous log collection.
  • Application Greylisting - Audit Mode

  • After monitoring these logs for as long as needed, the IT administrators can resolve the greylisted applications specific to a custom group. They can either be moved to a new or existing whitelist/blacklist depending on the frequency or legitimacy of their use.
  • Resolve greylisted applications

  • Once the greylist is resolved and the application whitelists are properly defined, the deployed policies can be modified to run in Strict Mode. This mode ensures heightened security as it only allows the whitelisted applications to run.
  • Greylisted Applications- Modify

    Application Greylisting- Strict Mode

Even though having the enterprise greylist application count at zero is ideal, enterprises aiming to take a more relaxed approach with application control can continue to run their policies in Audit Mode combined with proper monitoring.

With Application Control Plus, taking control doesn't stop with whitelisting and blacklisting. Stay one step ahead by keeping tabs on greylists as well. Try Application Control Plus free for a trial period of 30 days!