DMARC Mastery: Take Your Email Security to the Next Level

DMARC POLICIES: A Brief Overview

Before we delve into the best practices, let's briefly review the three DMARC policies and how they vary in protecting your domain:

1. None - In a traditional DMARC project, p=none is the first policy applied. This policy grants full visibility into how your domain is being used without impacting or influencing how your email is treated by email receivers. It provides zero protection but affords you the same visibility as the other, more restrictive policies.
2. Quarantine - p=quarantine is the second policy applied in a traditional DMARC project. This policy provides partial protection against unauthorized use of your domain and is a significant milestone in a DMARC project. It instructs email receivers to accept the message but downgrade the trustworthiness of the email and place it into the recipient’s spam/quarantine folder.
3. Reject - p=reject provides the highest level of protection against unauthorized use of your domain. This policy instructs email receivers to outright block emails that fail the DMARC check. Unlike p=quarantine, with p=reject, a message rejection notice is generated back to the sender. These blocking events are also made apparent in DMARC data, so you can readily observe how many messages are rejected and by what email source.

Key considerations for advancing your DMARC policy

Now that we have reviewed the DMARC policies, let's discuss some key considerations for advancing your DMARC policy:

1. Take it slow - Advancing your DMARC policy can be a gradual process, so it's essential to take it one step at a time. Start with p=none to gain full visibility into how your domain is being used. Once you're confident that your emails are being sent from authorized sources only, move on to p=quarantine.
2. Monitor your DMARC reports - Regularly monitor your DMARC reports to detect any potential issues and to determine if your policy is appropriately configured. Look out for any unusual sources sending emails from your domain and validate any new sources before advancing to the next policy.
3. Test your DMARC policy - It's essential to test your DMARC policy before making any changes. Testing can help you identify any potential issues before they cause any harm. Use a DMARC analyzer to test your policy, and adjust it as needed before applying it to your DNS.
4. Use DNS syntax guidelines - Use DNS syntax guidelines to ensure that your DMARC policy is appropriately configured. Syntax errors can cause your policy to fail, and DMARC data may not be properly reported.
5. Seek expert advice - DMARC policies can be complicated, and it's always a good idea to seek expert advice. Consult a DMARC expert to get insights into the best practices, and ask questions to clarify any doubts you may have.

Advancing your DMARC policy is a critical step toward improving your email security. It can be challenging, but following the best practices we have discussed can help you progress your domains towards a more stringent DMARC policy of p=reject. Remember to take it slow, monitor your DMARC reports, test your policy

How to prepare for DMARC policy progression

If you’re looking to advance your DMARC policies, there are a few things you need to consider. While it’s certainly a step in the right direction, progressing your DMARC policy too soon or without the proper visibility can actually result in blocked or degraded delivery of your legitimate email. So, what do you need to know before getting started?

Understanding the DMARC standard and email sources

First and foremost, it’s important to have a good understanding of the DMARC standard as well as visibility into your email sources. This means knowing where your emails are coming from and who they’re going to. It’s also recommended that you have at least four weeks’ worth of data to work with so that you can react accordingly.

Aligning your legitimate email sources

Another key consideration is aligning each of your legitimate email sources with DMARC. Alignment is essentially the relationship between the domain in the From Header address and the domains associated with SPF and DKIM records. In order for an email to pass DMARC, these domains need to match. So, if your domains aren’t aligned, your emails won’t pass DMARC.

Interpreting your DMARC compliance percentage rate

Once you’ve aligned your domains, you need to interpret your DMARC compliance percentage rate. This rate will tell you how well your emails are complying with DMARC. In most cases, you can start advancing your DMARC policy on a domain-by-domain basis once you’ve reached a compliance rate of 98% or higher.

However, if there’s an email source that you’re aware of but choose not to bring into alignment (perhaps the vendor doesn’t meet your internal policies/standards), you may be ready to progress your policy before reaching the 98% mark.

Scenario: Dealing with an unauthorized email vendor

Let’s say you’re part of an IT security staff responsible for the DMARC project, and you’ve just learned that someone within your organization is using a third-party email vendor to send shopping cart abandonment messages.

The problem is, this vendor was purchased by another team and failed to onboard according to your organization’s standards and policies. The vendor is unauthorized to send on behalf of your organization, and you need to address the issue.

Continuing to ramp up your DMARC policy

In this scenario, the IT security staff decides to continue ramping up their DMARC policy despite the unauthorized messages. While it’s unfortunate that these messages will be impacted, it’s important to maintain the integrity of your organization’s email practices. This means taking action to ensure that all email sources are aligned with DMARC and comply with your policies and standards.

Socializing your DMARC project

Finally, it’s important to socialize your DMARC project and keep your colleagues in the loop. Let them know about the progress you’ve made and provide a means for them to make an inquiry if they believe their email is being affected. This way, you can address any issues before they become a bigger problem.

Preparing for DMARC policy progression requires careful consideration of your email sources, alignment, compliance rate, and internal policies and standards. By taking these factors into account, you can advance your DMARC policy in a way that ensures the integrity of your email practices and improves your overall email deliverability.

Exploring DMARC's Percentage Tag: A Key Element for Gradual Implementation

As businesses continue to prioritize email security, implementing DMARC (Domain-based Message Authentication, Reporting, and Conformance) policies has become a crucial step in preventing email phishing and spoofing attacks. However, setting up a DMARC policy can be a daunting task, especially for those who are not familiar with email authentication protocols. In this article, we will explore one of the key elements of a DMARC record - the pct tag - and how it can help businesses gradually implement DMARC policies.

Understanding the Role of the pct Tag

The pct tag is a DMARC record element that specifies the percentage of emails that should be subjected to DMARC policy evaluation. Although it's not a mandatory element, including the pct tag can be beneficial in several ways.

Firstly, when the pct tag is not present in a DMARC record, the default value is 100%. This means that all emails from the specified domain will be subjected to DMARC policy evaluation. However, setting a lower percentage value can be helpful in gradually phasing in DMARC policies.

For instance, businesses can start by setting a 10% pct value, which means that only 10% of emails will be subjected to DMARC policy evaluation. This allows businesses to monitor and identify any potential issues that may arise without immediately blocking legitimate emails. Over time, the percentage value can be gradually increased to 20%, 30%, and so on until a 100% policy can be implemented confidently.

Additionally, the pct tag can help businesses discover necessary actions that need to be taken before implementing a 100% DMARC policy. By gradually increasing the percentage value, businesses can identify any issues with their email authentication setup and take necessary actions to address them.

When is the pct Tag Not Needed?

It's important to note that the pct tag is not necessary when implementing a p=none monitoring policy. This is because the p=none policy does not take any action on email flows. Instead, it simply reports on emails that pass or fail DMARC policy evaluation.

Recommendations for Using the pct Tag

When setting up a DMARC record, it's recommended to include the pct tag even if you're not planning to implement a gradual policy. This is because it provides flexibility for future policy changes.

If you're planning to implement a gradual policy, it's recommended to start with a lower percentage value and gradually increase it over time. This can help identify any issues and ensure a smooth transition to a 100% DMARC policy.

The pct tag is a crucial element of a DMARC record that can help businesses gradually implement DMARC policies while discovering necessary actions. By setting a lower percentage value, businesses can monitor and identify potential issues without immediately blocking legitimate emails. Overall, including the pct tag in a DMARC record provides flexibility and helps ensure a smooth transition to a secure email environment.

Progressing Your DMARC Policy

The progression of a DMARC policy is a gradual process that requires compliance from both your domains and email sources. Once you've achieved DMARC compliance, you can start advancing your policy from p=none to p=quarantine, and then to p=reject. To gain more control over your DMARC rollout, you can also take advantage of the optional percentage (pct) tag.

We recommend a cautious policy progression approach after ensuring your domains and sources is DMARC compliant. This schedule involves advancing your policies and increasing pct tags while closely monitoring your email flows to maintain a high DMARC compliance rate. It is generally recommended to maintain a DMARC compliance rate above 98% per domain.

To check a particular domain's DMARC compliance rate, we suggest using the Detail Viewer and filtering for the relevant domains. It's worth remembering that DMARC compliance is achieved by either SPF or DKIM passing and aligning. While the individual alignment scores of SPF or DKIM are not as crucial, the overall DMARC compliance rate is more important.

Here's an example of a DMARC p=quarantine policy with a 25% tag, where 25% of failing emails will go to spam and the remaining 75% will be at p=none:

v=DMARC1; p=quarantine; pct=25; rua=mailto:[email protected]

And here's an example of a DMARC p=reject policy with a 100% tag, where any email that fails DMARC authentication will be rejected by the receiving server:

v=DMARC1; p=reject; pct=100; rua=mailto:[email protected]

What You Should Know About DMARC's p=quarantine Policy

If you're implementing DMARC (Domain-based Message Authentication, Reporting, and Conformance) for your domain, you might be wondering what to expect when using the p=quarantine policy. Here's a breakdown of what you need to know:

Receivers Will Treat Failed Messages as Spam

Enforcing p=quarantine means that receivers will send messages that fail DMARC checks to the recipient's spam folder. However, it's important to keep in mind that receivers are likely to treat these messages the same way as spam, even if they're legitimate. If you're sending messages to consumer-oriented mailboxes like Gmail or Yahoo, they will be routed to the recipient's spam folder.

On the other hand, if you're sending messages to business-oriented mailboxes like Microsoft 365 or Google Workgroups, they may be routed to a quarantine holding area managed by the recipient's IT staff. Unfortunately, you won't have access to either of these environments to inspect what has been quarantined, except for mail destined for your own organization.

To get a better understanding of what messages are being quarantined, you can use DMARC platforms to identify mailstreams and track the frequency of quarantined messages.

The Impact of p=quarantine is Observed by Receivers

Only receivers will notice when email suddenly starts being treated as spam or isolated into an email quarantine system. There are no notifications sent to the senders. To monitor the impact of p=quarantine, you can use the DMARC platform's to track the rate of quarantined or rejected mail, which can help you identify successes, gaps in authentication, and sending patterns.

p=quarantine is a Useful Policy to Test DMARC Deployment

While p=quarantine can provide you with valuable data points to test your DMARC deployment, keep in mind that the most secure state of domain protection is achieved with a policy of p=reject at 100%. This policy will prevent unauthenticated messages from being delivered from your domain.

Even if you don't have DMARC in place, receivers will still do what they think is appropriate, and some fraudulent messages may get rejected. With DMARC, you have control and can make the determination of what to do with unauthenticated messages, instead of leaving the decision up to the receiver.

In conclusion, if you're implementing DMARC for your domain, it's important to understand the implications of using the p=quarantine policy. While it can help you test your DMARC deployment and gather useful data, it's not the most secure state of domain protection.

Consider using a policy of p=reject at 100% to prevent unauthenticated messages from being delivered from your domain. By taking control of the authentication process, you can ensure that your legitimate messages are delivered and that your domain is protected from fraudulent messages.

Get Ready for the Implications of p=reject DMARC Policy

By implementing a DMARC enforcement policy with p=reject, you instruct the receiver to permanently reject any incoming email that fails DMARC authentication. This could result in a 5XX series hard bounce message being generated and communicated back to the sending server, indicating that the email has been rejected.

To ensure that you stay on top of any rejected messages, we highly recommend that you establish a regular cadence of checking your DMARC data for any pattern changes. By adopting a p=reject policy, you'll have the ultimate protection against unauthenticated emails, including shadow IT and malicious emails that may originate from your domain. So, brace yourself for the implications of this powerful security measure.

Maximizing DMARC Compliance: Best Practices for Maintaining p=reject Status

Once you have successfully enforced your DMARC policy to p=reject, it’s time to focus on long-term DMARC management to maintain compliance and minimize potential issues. The Life after Reject phase of the DMARC project is crucial for ensuring continued success in email deliverability. In this article, we’ll discuss some essential best practices for managing your DMARC compliance.

Periodic SPF Record Checks

SPF records should be regularly reviewed to ensure they are up-to-date and accurately represent the authorized IPs or netblocks that can send email on behalf of your organization. By using an SPF Surveyor, you can quickly identify any outdated or over-authenticated records, which could negatively impact your email deliverability. Review the contents of your record for any vendors you no longer use or were added in error previously.

Process of Approving SPF Changes

It's important to establish a process for approving any changes to your SPF records. Ensure that no changes are made without the approval of the DMARC project owner at your organization. Create alerts to notify you when any unexpected changes have taken place to avoid unauthorized changes to your records.

Monitoring Periodic DKIM Key Rotation

To maintain DMARC compliance, DKIM keys should be rotated on a regular basis, depending on your organization's specific needs. Typically, this should be done every few months or annually. Regular key rotation can help prevent attacks by ensuring that old keys cannot be used to send fraudulent emails.

Periodic Check of DMARC Data

Regularly checking your DMARC data can help you identify new sources of legitimate email and detect any compliance regressions at a particular vendor or unexpected delivery patterns. Tracking vendor consolidation opportunities and email volume changes can also help you optimize your email deliverability.

Reporting

Configure your ESP to send reports about the use and abuse of your domains. By doing this, you can gain insight into how your domains are being used and identify any unauthorized use. These reports can also help you maintain DMARC compliance by identifying issues and solutions.

Internal Incident Management

If you suspect email deliverability issues are DMARC-related, you can filter your DMARC data to understand the reach of the issue. This will help you diagnose the problem and find solutions quickly. Establishing an internal incident management process can help you respond quickly to any issues that arise.

In conclusion, by following these best practices for DMARC compliance management, you can maintain your p=reject status and ensure successful email deliverability. Remember to periodically review your SPF records, establish a process for approving changes, monitor periodic DKIM key rotation, check your DMARC data, configure reporting, and establish an internal incident management process.

With these practices in place, you can stay ahead of potential DMARC compliance issues and maintain successful email deliverability.