Stop Password Spray Attacks with Authentication Policies

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Using Authentication Policies to Protect Against Password Spray Attacks
Password spray attacks are an increasingly common method used by attackers to gain access to an organization’s resources. In these attacks, attackers try to guess a user’s password by trying a large number of commonly used passwords. These attacks are difficult to detect and can be very successful if the user’s password isn’t strong enough.

What is an Authentication Policy?
An authentication policy is a set of rules that define how users authenticate to an organization’s resources. Authentication policies can be used to protect against password spray attacks by limiting the number of password attempts that can be made in a specified period of time.

Using Authentication Policies to Protect Against Password Spray Attacks
Using an authentication policy can help protect against password spray attacks by limiting the number of password attempts that can be made in a specified period of time. The policy should be configured so that after a certain number of failed attempts, the user is blocked from attempting to authenticate again for a certain period of time. This will help thwart the attacker’s attempts to guess the user’s password.

How to Configure an Authentication Policy
Authentication policies can be configured using the Microsoft Exchange Admin Center (EAC). To configure an authentication policy, follow these steps:

Step 1: Log into the Microsoft Exchange Admin Center
Log into the EAC using your administrative credentials.

Step 2: Navigate to the Authentication Policies section
Once you are logged in, navigate to the Permissions > Authentication Policies section.

Step 3: Create a New Authentication Policy
Once you are in the Authentication Policies section, click the “+” button to create a new policy. Give the policy a name, and then select the users that the policy will apply to.

Step 4: Configure the Policy Settings
In the policy settings, configure the maximum number of failed attempts and the time period for which the user will be blocked from attempting to authenticate again.

Step 5: Apply the Policy
Once you have configured the policy settings, click the “Save” button to apply the policy.

Conclusion
Password spray attacks are an increasingly common method used by attackers to gain access to an organization’s resources. Authentication policies can be used to protect against these attacks by limiting the number of password attempts that can be made in a specified period of time. To configure an authentication policy, log into the Microsoft Exchange Admin Center, navigate to the Authentication Policies section, create a new policy, configure the policy settings, and then apply the policy.
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Use Authentication Policies to Fight Password Spray Attacks