As email continues to be a critical communication channel, DMARC policy for businesses and individuals alike will only continue to grow in importance. DMARC, in full means Domain-based Message Authentication, Reporting, and Conformance. It represents a significant leap forward in email security.
DMARC provides a framework for email domain owners to publish policies on how their emails should be authenticated, helping create a more trustworthy email ecosystem. Implementing DMARC means organizations can proactively protect their brand, employees, and customers from email-based threats.
And while it’s not a cure-all for all email-related security issues, DMARC is a crucial tool in the fight against phishing and email spoofing attacks. In this article, we explore DMARC policy, how to implement it, the challenges and benefits, and why you should opt for our hosted DMARC solution for policy implementation.
What is a DMARC Policy?
DMARC policy is an email validation system that uses Domain Name System (DNS) to instruct receiving mail servers on how to handle emails claiming to be from your own domain but failing authentication checks. It is denoted by the “p” tag in the DMARC record that specifies the action mail servers should take if an email fails DMARC validation.
A properly implemented policy can help you determine how strictly you want to handle emails that might try to impersonate your brand. Consider it a security guard for your organizational domain. Depending on your ID, the guard determines whether he lets you into the building (in this case, your receiver’s inbox). He may prevent you from stepping in (reject), he may send you to a special place for further review (quarantine), or he may just let you in (none).
Your DMARC policy when set to p=reject can help you prevent spoofing, phishing, and domain name abuse, acting like a “no-trespassing” sign for bad actors trying to impersonate your brand.
The 3 DMARC Policy Options: None, Quarantine, and Reject
The three DMARC policy types are:
1. DMARC None:
A “monitoring only” policy that serves no protection. It’s good for the beginning stages of your deployment journey. Emails are delivered but reports are generated for unauthenticated messages. In the DMARC record, this would be denoted by “p=none”.
2. DMARC Quarantine:
Suspicious emails are flagged and placed in the recipient’s spam folder for review. In the DMARC record, this would be denoted by “p=quarantine”.
3. DMARC Reject:
The strictest optionit instructs receiving servers to completely reject unauthenticated emails. In the DMARC record, this would be denoted by “p=reject”.
Which one you use depends on the level of enforcement email domain owners want to establish. The main difference between these policy options is determined by the action taken by the receiving mail transfer agent when adhering to the specified policy defined by the mail sender in their DNS records.
1. DMARC Policy: None
DMARC policy none (p=none) is a relaxed mode that triggers no action on the receiver’s side. This policy can be used to monitor email activity and is typically used during the initial DMARC implementation phase for monitoring and data collection.
It doesn’t provide any level of protection against cyberattacks and allows all messages to be delivered, regardless of authentication results. This option is specified in the DMARC record using the “p=none” tag.
Example: v=DMARC1; p=none; rua= mailto:(email address);
None Policy Implementation Use Cases
- The main aim of domain owners who select the “none” policy should be to gather information on sending sources and keep a tab on their communications and deliverability without any inclination towards strict authentication. This may be because they are not yet prepared to commit to enforcement, and are taking their time to analyze the current situation.
- Receiving email systems treat messages sent from domains configured with this policy as “no-action”, meaning that even if these messages fail the DMARC policy, no action will be taken to discard or quarantine them. These messages will successfully reach your clients.
- DMARC reports are still generated when you have “p=none” set up. The recipient’s MTA sends aggregate reports to the organizational domain owner, providing detailed email authentication status information for the messages that appear to originate from their domain.
2. DMARC Policy: Quarantine
This option is specified in the DMARC record using the “p=quarantine” tag. p=quarantine provides some level of protection as the domain owner can prompt the receiver to roll back emails into the spam or quarantine folder to review later in case DMARC fails.
This policy instructs the receiving mail server to treat messages that fail DMARC authentication with suspicion. It is often implemented as an intermediate step between “none” and “reject”.
Example: v=DMARC1; p=quarantine; rua=mailto:(email address);
Quarantine Policy Implementation Use Cases
- Rather than outright discarding unauthenticated emails, the “quarantine” policy offers the ability for domain owners to maintain security while also providing the option to review emails before accepting them, taking the “verify then trust” approach.
- Changing your DMARC policy to DMARC quarantine ensures that legitimate messages that fail DMARC authentication will not be lost before you closely inspect them.
- This approach can be considered intermediate in terms of enforcement and facilitates a smooth transition to p=reject, wherein domain owners can:
a) Assess the impact of DMARC on your email messages
b) Make informed decisions regarding whether or not they should discard the flagged emails. - The quarantine policy also helps reduce inbox clutter, ensuring your inbox doesn’t get overloaded with messages in the spam folder.
3. DMARC Policy: Reject
This option is specified in the DMARC record using “p=reject”. This is the strictest policy, telling receivers to reject unauthenticated messages.
DMARC policy reject provides maximum enforcement, ensuring messages that fail DMARC checks are not delivered at all. The policy is implemented when domain owners are confident in their email authentication setup.
Example: v=DMARC1; p=reject; rua= mailto:(email address);
Reject Policy Implementation Use Cases
- DMARC policy reject enhances your email security. It can prevent attackers from launching phishing attacks or direct domain spoofing. DMARC’s reject policy stops fraudulent emails by blocking out messages that appear suspicious.
- If you are confident enough not to quarantine suspicious messages, the “reject” policy is suitable for you.
- It is important to thoroughly test and plan before opting for DMARC reject.
- Make sure DMARC reporting is enabled for your domain when on DMARC reject.
- To DIY your enforcement journey, start at p=none and then slowly move to reject while monitoring your daily reports.
Other DMARC Policies
DMARC offers additional policy parameters to fine-tune implementation.
- The percentage (pct=) parameter allows gradual policy rollout by specifying the portion of messages subject to DMARC.
For example: pct=50 applies the policy to 50% of messages. - The subdomain policy (sp=) is a policy record that sets separate rules for subdomains. It is useful when subdomains require different handling.
For example: v=DMARC1; p=reject; sp=quarantine; rua=mailto:dmarc-reports@example.com`
Setup DMARC Policy the right way with PowerDMARC!
Why DMARC Matters
Emails can be easily forged, making it hard to tell the real deal from a dangerous fake. That’s where DMARC comes in. DMARC is like an email security checkpoint that verifies the sender’s identity before letting messages through.
Forbes estimates that the cost associated with cybercrime will reach $10.5 trillion annually by 2025. Meanwhile, Verizon reports that more than 30% of all data compromises are a result of phishing attacks, highlighting the need for powerful protection like DMARC.
According to RFC 7489 of the IETF, DMARC has the unique ability to allow email senders to set preferences for authentication. By enabling it, you can also get reports on email handling and potential domain abuse. This makes DMARC stand out in terms of domain validation.
As per our latest DMARC statistics, a significant number of domains are still vulnerable to phishing attacks due to a lack of DMARC implementation.
To start the setup process for DMARC, a proper DNS changes and include DNS TXT records for the protocols. However, manual implementation of the DMARC protocol can be quite complex for non-technical users. It may even get quite costly if you hire an external fractional CISO to manage it for your business. PowerDMARC’s DMARC analyzer is therefore an easy alternative. With our DMARC analyzer, we automate your DMARC policy setup, saving you both time and money.
DMARC Reporting Options
Reporting options for DMARC include:
- Aggregate reports (rua=) for high-level data on authentication results and sending sources.
- Forensic reports (ruf=) for detailed authentication failure information.
These parameters enable organizations to gather valuable insights on DMARC authentication results, giving insight into the number of emails that fail or pass DMARC authentication. A DMARC report also helps:
- Identify potential issues and patterns of abuse
- Detect misconfigurations in their email setup
- Gain insights into email behavior and mail flows
- Review authentication results for SPF and DKIM protocols
Common Benefits & Challenges in DMARC Implementation
While DMARC offers significant benefits for email security, organizations often face several challenges during implementation. This is the reason most people opt for our Hosted DMARC–a service that helps you configure, monitor, and update your DMARC solution easily on a cloud platform.
Implementing DMARC policies in a real-world scenario typically follows a phased approach. This method allows organizations to gradually tighten their email security while minimizing the risk of disrupting legitimate email flow.
You can follow our guide on how to implement DMARC as a DIY policy enforcement. However, ideally, we recommend that you opt for our hosted DMARC solution to get expert assistance. Our professionals guide your DMARC implementation and throughout your enforcement journey.
Troubleshoot DMARC Policy Errors
When using DMARC, you may encounter an error message. The following are some common DMARC policy errors:
- Syntax Errors: You should be wary of any syntax errors while setting up your record to make sure that your protocol functions correctly.
- Configuration Errors: Errors while configuring the DMARC policy are common and can be avoided by using a DMARC checker tool.
- DMARC sp Policy: If you configure a DMARC reject policy, but set up your subdomain policies to none, you will not be able to achieve compliance. This is due to a policy override on your outbound emails.
- “DMARC Policy Not Enabled” Error: If your domain reports highlight this error, it points to a missing DMARC domain policy in your DNS or one that is set to “none”. Edit your record to incorporate p=reject/quarantine and this should fix the problem.
DMARC Policy Enforcement with PowerDMARC
PowerDMARC’s DMARC analyzer platform helps you effortlessly set up the DMARC protocol. Use our cloud-native interface to monitor and optimize your records with a few clicks of a button. Contact us today to implement a DMARC policy and monitor your results easily!
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Our Content and Fact-Checking Review Process
This piece of content was authored by a cybersecurity expert. It has been meticulously reviewed by our in-house security team to ensure technical accuracy and relevance. All facts have been verified against official IETF documentation. References to reports and statistics that support the information are also mentioned.
- Email Phishing and DMARC Statistics - November 22, 2024
- DMARC Compliance and Requirements - November 21, 2024
- What Is DMARC Policy? None, Quarantine And Reject - September 15, 2024