Share via

Best practice for AD CS certificate templates requiring custom Subject Name without introducing security vulnerabilities

Anant Bera 251 Reputation points
2025-12-18T10:31:46.6366667+00:00

Hi Experts,

In AD CS certificate templates, there are certain scenarios where the Subject Name must be supplied in the request (for example, to include specific organizational details such as Organization, OU, or a custom CN).

However, enabling “Supply in the request” for the Subject Name is commonly flagged by security assessment tools (e.g., ESC1/ESC4-related findings) because it can allow abuse if permissions are weak or misconfigured.

When a business or application genuinely requires a custom Subject Name in an AD CS certificate template:

  • What are the recommended best practices to implement this securely?
  • How can this requirement be met without introducing AD CS vulnerabilities?
  • Are safer alternatives commonly used, such as:
    • Using SAN instead of Subject Name
    • Restricting template permissions to tightly scoped security groups
    • Enforcing manager approval or additional issuance controls
    • Using separate, dedicated templates for these scenarios

Thanks in Advance

Sysinternals
Sysinternals
Advanced system utilities to manage, troubleshoot, and diagnose Windows and Linux systems and applications.
0 comments

1 answer

Sort by: Most helpful
Most helpful Newest Oldest
  1. Q&A Assist
    2025-12-18T10:32:00.24+00:00
    AI generated content. This question contains an answer created with AI from Q&A Assist. Learn more

    To securely implement custom Subject Names in Active Directory Certificate Services (AD CS) certificate templates while minimizing security vulnerabilities, consider the following best practices:

    1. Use Subject Alternative Names (SAN): Instead of relying on the Subject Name, utilize the SAN field, which allows for multiple entities to be included in the certificate without exposing the system to the same level of risk associated with the Subject Name.
    2. Restrict Template Permissions: Ensure that the permissions for the certificate template are tightly scoped. Limit enrollment permissions to specific, trusted security groups rather than allowing broad access to unprivileged users. This helps prevent unauthorized certificate requests that could exploit the template.
    3. Enforce Manager Approval: Implement a requirement for manager approval or additional issuance controls for certificate requests. This adds a layer of oversight and helps ensure that only legitimate requests are processed.
    4. Use Separate, Dedicated Templates: Consider creating separate certificate templates specifically for scenarios that require custom Subject Names. This allows for more granular control over the permissions and settings associated with those templates, reducing the risk of misconfiguration.
    5. Review and Monitor: Regularly review the configurations and permissions of your certificate templates. Monitoring for any unauthorized changes or access attempts can help identify and mitigate potential security issues before they become serious threats.

    By following these practices, you can meet the requirement for custom Subject Names in a secure manner, reducing the risk of vulnerabilities associated with AD CS configurations.

    References:

    0 comments

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.