If you have any interest in email marketing, you’ve likely heard of DMARC. Short for Domain-based Message Authentication, Reporting & Conformance, DMARC is an email-validation system that detects and prevents email spoofing.
It helps protect your email domain against phishing attacks and increases email deliverability.
But how does it work? And why should you care about it?
What is DMARC?
DMARC, or Domain-based Message Authentication, Reporting & Conformance, is your organization’s first line of defense against cyberattacks, utilizing standard authentication protocols like Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) to identify and prevent malicious emails posing as legitimate ones from your domain.
Basically, DMARC acts as a shield for your organization’s communication channels, proactively fighting off email spoofing. It’s important to understand that DMARC isn’t an optional tool but a necessity, especially when it comes to email marketing. Most ESPs now require users to have a valid DMARC to send emails.
How does DMARC work?
To understand how DMARC works, it’s important to know that it relies on the results of SPF and DKIM, which must be in place for your email domain. You need to publish a DMARC record in your domain’s DNS to implement DMARC. This record is a text entry that communicates your domain’s policy after checking SPF and DKIM status. If either SPF, DKIM or both pass, DMARC authenticates it. This process is referred to as DMARC alignment or identifier alignment.
In addition, the DMARC record instructs email servers to send XML reports back to the reporting email address listed in the DMARC record. These reports provide a detailed analysis of your email’s journey through the ecosystem and help identify all users of your domain.
However, deciphering XML reports can be complex and you may receive many of them. Tools like dmarcian’s DMARC Management Platform can help by visualizing these reports, allowing you to understand how your email domains are used, and enabling you to shift your DMARC policy towards p=reject.
Why Use DMARC for Email?
Now that you understand how DMARC works, let’s talk about why it’s important for email security. DMARC is useful in protecting against cyber attacks, which involve email over 90% of the time. With DMARC, you can distinguish real emails from fake ones, protecting your domain from unauthorized use, phishing, spoofing, CEO fraud, and Business Email Compromise.
By consistently sending DMARC-compliant emails, you signal to other networks that your emails are identifiable and trustworthy. This verification tells them to reject any fraudulent emails pretending to be yours. Instead of attempting to filter out malicious emails, DMARC focuses on making legitimate emails easily identifiable. This strategy replaces the flawed ‘filter out bad’ model with a more efficient ‘filter in good’ model.
If you’re ever unsure about the health of your domain, consider using a free domain checker. These tools inspect your DMARC, SPF, and DKIM, providing you with necessary actions to achieve compliance.
What does a DMARC record look like?
So, you may be wondering what a DMARC record even looks like in your domain’s DNS records. These records are published in the DNS as TXT records, with the name set as ‘_dmarc.yourdomain.com,’ replacing ‘yourdomain.com’ with your actual domain name.
A DMARC record might look like this:
v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com; ruf=mailto:dmarc@yourdomain.com; sp=none; fo=1; pct=100; rf=afrf
Key Components of a DMARC Policy
- v (Version): Specifies the DMARC protocol version. In this case, “DMARC1” indicates the version of the DMARC protocol being used.
- p (Policy): Defines the policy to be applied to emails that fail the DMARC check. The “none” setting means the domain owner is in monitoring mode, focusing on collecting data through DMARC reports without affecting email delivery. Other options include “quarantine” (move failing emails to spam/junk) and “reject” (block failing emails).
- rua (Reporting URI of Aggregate reports): Specifies where aggregate reports of DMARC checks should be sent. The URI provided, “mailto:dmarc@yourdomain.com“, indicates an email address where these summary reports are to be delivered. These reports give a broad overview of email authentication success and failures over a period.
- ruf (Reporting URI of Forensic reports): Points to the destination for forensic reports, which are detailed reports on individual email failures. Like “rua”, the URI “mailto:dmarc@yourdomain.com” specifies an email for receiving these more detailed insights.
- sp (Subdomain Policy): Indicates the policy for handling DMARC failures from emails originating from subdomains of the main domain. In this example, “none” applies the same monitoring approach to subdomains, not enforcing quarantine or reject actions but allowing data collection.
- fo (Forensic options): Determines the conditions under which forensic reports are generated. “1” means reports will be sent if either DKIM or SPF checks fail, providing granular data for troubleshooting and improving email authentication practices.
- pct (Percentage): Specifies the percentage of messages subject to the DMARC policy. “100” means all failing emails are considered under the specified DMARC policy. Note that this is most impactful with “quarantine” or “reject” policies, as “none” inherently does not alter email handling.
- rf (Reporting Format): Defines the format for forensic reports. “afrf” stands for Authentication Failure Reporting Format, a standardized format for these detailed reports.
DMARC Policies: None, Quarantine, Reject
None (p=none)
- What It Does: The
nonepolicy is essentially a monitoring mode. When emails fail DMARC checks, no action is taken to alter their delivery. Emails that fail authentication are still delivered to recipients’ inboxes. - Why Use It: The primary purpose of the
nonepolicy is to observe and collect information about your email sending practices without affecting email deliverability. It allows domain owners to identify legitimate sources of email and potential authentication issues, as well as to detect unauthorized use of their domain. - Considerations: While it doesn’t protect against fraudulent emails being delivered, it’s an essential first step in DMARC implementation. It helps ensure that your legitimate emails are correctly authenticated (and won’t be affected by stricter policies) before moving to more restrictive policies like
quarantineorreject.
Quarantine (p=quarantine)
- What It Does: With the
quarantinepolicy, emails that fail DMARC checks are moved to the spam or junk folder, rather than the recipient’s inbox. - Why Use It: This policy increases protection against phishing and spoofing by preventing unauthenticated emails from being directly delivered to inboxes. It still allows recipients to review these emails if necessary, mitigating the risk of legitimate emails being completely lost due to false positives.
- Considerations: It’s a middle-ground approach that balances security with deliverability. When implementing
quarantine, it’s essential to monitor feedback and reports closely to adjust your email authentication practices as needed and to ensure legitimate emails are not being quarantined.
Reject (p=reject)
- What It Does: The
rejectpolicy is the most stringent. Emails failing DMARC checks are completely refused delivery; they are not delivered to the recipient’s mailbox or even to the spam/junk folder. - Why Use It: This policy offers the highest level of protection against email fraud by ensuring that only authenticated emails are delivered. It’s effective in protecting users from potential phishing attacks and maintaining the integrity of your domain’s email communications.
- Considerations: Before implementing a
rejectpolicy, it’s critical to have a well-configured email authentication setup (SPF, DKIM, and initially DMARC withnonepolicy) to minimize the risk of legitimate emails being rejected. Continuous monitoring and management of your email sources and authentication records are crucial to prevent disruption of legitimate email traffic.
Transitioning Between Policies
It’s common practice to start with a none policy to gather data and ensure that legitimate email sources are properly authenticated and aligned. Gradually, as confidence in the email authentication setup grows, transitioning to quarantine and eventually to reject can provide increasing levels of protection against email fraud and abuse.
Each policy setting serves different stages in the DMARC implementation process, from initial observation and data collection (none), to intermediate protection with room for manual review (quarantine), and finally to full protection and prevention of delivery for unauthenticated emails (reject).
There are three possible DMARC policies: none (monitoring only), quarantine, and reject. The ‘none’ policy enables you to get DMARC reports, without affecting email deliverability. These policies are identified by the “p=” part of the record.
The ‘quarantine’ policy, in addition to sending reports, directs email systems to deliver non-DMARC compliant emails into the spam folder. This mitigates the impact of spoofing, but spoofed emails still reach the receiver’s spam folder.
What are the benefits of DMARC email security?
Now that we’ve covered the structure and policies of a DMARC record, let’s consider the advantages of implementing DMARC email security within your organization.
- Prevention of Phishing and Spoofing Attacks: DMARC’s primary function is to protect your organization from cyber threats. It adds an extra layer of security by verifying the sender’s identity, thereby preventing phishing and certain spoofing attacks. This significantly reduces the risk of your organization falling victim to fraudulent activities.
- Greater Visibility: DMARC provides insight into all emails sent from your organization’s domain or from third-party providers your organization uses. This visibility offers a detailed overview of your email ecosystem, allowing you to monitor and manage all outbound communications effectively.
- Troubleshooting Delivery Issues: DMARC is instrumental in identifying issues with email authentication through SPF and DKIM. By providing real-time alerts, it enables prompt detection and resolution of delivery issues, ensuring your emails reach their intended recipients without unnecessary delays or disruptions.
Free DMARC Checker Tools
If you aren’t sure if your DMARC record is implemented correctly, you can use a variety of free DMARC checker tools to make sure your DMARC record is valid and correct.
MxToolbox, EasyDMARC, and DMARCLY are some of the leading options in this domain.
Each tool carries its own unique set of features, allowing you to optimize your DMARC deployment and streamline your email security.
MxToolbox
MxToolbox is another reliable source for free DMARC checker tools, designed to enhance your email security by pinpointing potential vulnerabilities in your DMARC, SPF, and DKIM configurations.
- DMARC Checker: This tool analyzes your DMARC record for syntax errors, ensuring it’s correctly published on your DNS. It’s crucial to get this right to prevent spoofing and phishing attempts.
- SPF Record Checker: It checks if your SPF record is valid and aligned with the DMARC policy. A misconfiguration here could lead to email delivery problems.
- DKIM Record Checker: This verifies the existence and validity of your DKIM record, which authenticates your emails, thereby building trust with recipients.
In essence, MxToolvbox offers a comprehensive, free solution to scrutinize and enhance your email security setup.
EasyDMARC
EasyDMARC offers a suite of free DMARC checker tools that provide robust and detailed analysis of your DMARC records.
This toolset is instrumental in identifying, understanding, and reacting to email threats faster. EasyDMARC’s tools look into your DMARC data, providing insights into your domain’s compliance, sources of email, and threat patterns.
The tool offers an interactive graphical interface that simplifies the process of tracking your email delivery status, making it easier to understand and interpret the data effectively.
Besides, it automatically generates aggregate reports for easy monitoring and management of your email domain.
With EasyDMARC, you’re not just improving your email security but also increasing your domain’s reputation and deliverability.
DMARCLY
Similar to EasyDMARC, DMARCLY offers another set of free DMARC checker tools that can significantly enhance your domain’s email security.
DMARCLY’s tools ensure you’re at the forefront of maintaining a secure email environment by:
- DMARC Analyzer: This tool provides comprehensive reports on DMARC alignment failures. It pinpoints the source of the failure, helping you identify problem areas and fix them.
- DMARC Record Generator: It creates a DMARC record for your domain, tailored to your specific security needs.
- DMARC Record Lookup: This tool checks if your domain has a valid DMARC record and verifies its correctness.
DMARCLY’s tools provide detailed, analytical data to help you safeguard your domain’s email security, effectively making your email environment more
