Network access: Do not allow storage of passwords and credentials for network authentication

Applies to

  • Windows 11
  • Windows 10

Describes the best practices, location, values, policy management and security considerations for the Network access: Do not allow storage of passwords and credentials for network authentication security policy setting.

Reference

This security setting determines whether Credential Manager saves passwords and credentials for later use when it gains domain authentication.

Possible values

  • Enabled

    Credential Manager doesn't store passwords and credentials on the device

  • Disabled

    Credential Manager will store passwords and credentials on this computer for later use for domain authentication.

  • Not defined

Best practices

It's a recommended practice to disable the ability of the Windows operating system to cache credentials on any device where credentials aren't needed. Evaluate your servers and workstations to determine the requirements. Cached credentials are designed primarily to be used on laptops that require domain credentials when disconnected from the domain.

Location

Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options

Default values

The following table lists the actual and effective default values for this policy. Default values are also listed on the policy’s property page.

Server type or Group Policy Object (GPO) Default value
Default domain policy Disabled
Default domain controller policy Disabled
Stand-alone server default settings Disabled
Domain controller effective default settings Not defined
Member server effective default settings Not defined
Effective GPO default settings on client computers Not defined

Policy management

This section describes features and tools that are available to help you manage this policy.

Restart requirement

A restart of the device is required before this policy will be effective when changes to this policy are saved locally or distributed through Group Policy.

Group Policy

This policy setting can be configured by using the Group Policy Management Console (GPMC) to be distributed through Group Policy Objects (GPOs). If this policy isn't contained in a distributed GPO, this policy can be configured on the local computer by using the Local Security Policy snap-in.

Security considerations

This section describes how an attacker might exploit a feature or its configuration, how to implement the countermeasure, and the possible negative consequences of countermeasure implementation.

Vulnerability

Passwords that are cached can be accessed by the user when logged on to the device. Although this information may sound obvious, a problem can arise if the user unknowingly runs malicious software that reads the passwords and forwards them to another, unauthorized user.

Note:  The chances of success for this exploit and others that involve malicious software are reduced significantly for organizations that effectively implement and manage an enterprise antivirus solution combined with sensible software restriction policies.

Regardless of what encryption algorithm is used to encrypt the password verifier, a password verifier can be overwritten so that an attacker can authenticate as the user to whom the verifier belongs. Therefore, the administrator's password may be overwritten. This procedure requires physical access to the device. Utilities exist that can help overwrite the cached verifier. With the help of one of these utilities, an attacker can authenticate by using the overwritten value.

Overwriting the administrator's password doesn't help the attacker access data that is encrypted by using that password. Also, overwriting the password doesn't help the attacker access any Encrypting File System (EFS) data that belongs to other users on that device. Overwriting the password doesn't help an attacker replace the verifier, because the base keying material is incorrect. Therefore, data that is encrypted by using Encrypting File System or by using the Data Protection API (DPAPI) won't decrypt.

Countermeasure

Enable the Network access: Do not allow storage of passwords and credentials for network authentication setting.

To limit the number of cached domain credentials that are stored on the computer, set the cachedlogonscount registry entry. By default, the operating system caches the verifier for each unique user's 10 most recent valid logons. This value can be set to any value between 0 and 50. By default, all versions of the Windows operating system remember 10 cached logons, except Windows Server 2008 and later, which are set at 25.

When you try to sign in to a domain from a Windows-based client device, and a domain controller is unavailable, you don't receive an error message. Therefore, you may not notice that you logged on with cached domain credentials. You can set a notification of a sign in that uses cached domain credentials with the ReportDC registry entry.

Potential impact

Users are forced to type passwords whenever they sign in to their Microsoft Account or other network resources that aren't accessible to their domain account. This policy setting should have no impact on users who access network resources that are configured to allow access with their Active Directory–based domain account.