What is the purpose of the 'rua' tag in a DMARC record?

The 'rua' tag specifies the email address where DMARC aggregate reports should be sent. These reports provide XML-formatted data on email authentication results for your domain, helping you monitor legitimate and fraudulent email activity.

What happens if I forget the 'mailto:' prefix?

If the 'mailto:' prefix is omitted, email receivers will not recognize the address as a valid destination for reports, and your DMARC aggregate reports will not be delivered. This leaves you without crucial insights into your email authentication and potential spoofing attempts.

Can I send DMARC reports to an email address on a different domain?

Yes, you can send DMARC reports to an external domain. You still need the 'mailto:' prefix for the email address in your 'rua' tag. The receiving domain must also have a DMARC record that authorizes your domain to send reports to it, often involving a TXT record in their DNS.

How can I easily ensure my DMARC 'rua' URI is correctly configured?

Using a DMARC record generator or a DMARC monitoring platform like Suped can help. These tools automatically format the 'rua' URI correctly and validate your entire DMARC record to prevent errors.

Does a DMARC 'rua' URI require 'mailto:' prefix? - DMARC - Email authentication - Knowledge base

An email being stamped with the text 'mailto:' indicating the DMARC 'rua' URI requirement.

When configuring a DMARC record, one of the crucial elements for receiving aggregate reports is the rua tag. This tag specifies where XML reports, detailing email authentication results, should be sent. A common question arises regarding the format of the email address within this tag: does it require a 'mailto:' prefix? The short answer is yes, it absolutely does.

This prefix is not merely a suggestion, but a fundamental requirement for the DMARC standard. Without it, your email authentication reports will not be delivered, leaving you blind to potential spoofing attempts and deliverability issues. Understanding why this prefix is essential helps in correctly setting up and maintaining a robust DMARC policy for your domains.

Understanding DMARC RUA reports

DMARC aggregate reports are invaluable for monitoring your email ecosystem. They provide a high-level overview of all mail sent from your domain, including legitimate mail and any attempts at spoofing. These reports offer insights into which emails pass SPF and DKIM authentication, and which fail, helping you identify unauthorized senders.

The rua tag in your DMARC record specifies the address where these reports should be sent. This allows you to gather data from various email receivers (like

Google, Yahoo, Outlook) and analyze them using a DMARC monitoring platform. Without these reports, it is difficult to accurately assess your email security posture and make informed decisions about your DMARC policy.

Typical DMARC record with RUA

A DMARC record must be published as a TXT record in your DNS. Here's what a typical DMARC record with the 'rua' tag looks like:

DMARC DNS TXT Record ExampleDNS

v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com; fo=1;

Notice the mailto: prefix before the email address. This is critical for receivers to understand that the URI provided is an email address for report delivery.

Platforms like Suped simplify the process of configuring your DMARC records and analyzing the incoming reports, offering actionable recommendations to improve your email security.

The 'mailto:' prefix requirement

The 'mailto:' prefix is a mandated component of a Uniform Resource Identifier (URI) for email addresses, as defined in RFC 3986. When the DMARC protocol was designed, it adopted the URI scheme for specifying report destinations. For an email address, the URI scheme requires the 'mailto:' prefix to designate it as an email resource.

Email receivers, such as Gmail and Yahoo, strictly adhere to this standard. If the 'mailto:' prefix is missing from the 'rua' (or 'ruf') tag in your DMARC record, the receiving mail servers will not recognize the specified address as a valid destination for reports. This means your reports will simply not be sent to you, causing a critical gap in your email monitoring.

Correct RUA Syntax	Incorrect RUA Syntax
Includes the mailto: prefix.	Omits the mailto: prefix.
Example: rua=mailto:reports@example.com	Example: rua=reports@example.com
Reports will be delivered correctly.	Reports will not be delivered, leading to monitoring failures.

This adherence to standard URI formatting is why tools like the Suped DMARC record generator automatically include this prefix to ensure proper configuration from the start.

Impact of omitting 'mailto:'

Omitting the 'mailto:' prefix in your 'rua' URI will lead to a complete failure in receiving DMARC aggregate reports. Mail servers will not recognize the provided string as a valid email address and will consequently not forward any reports. This leaves your domain vulnerable and your deliverability efforts unmonitored.

Without these reports, you cannot track email authentication failures, meaning you will not be aware if your domain is being spoofed or if your legitimate emails are failing DMARC checks. This lack of visibility can hinder your ability to reach the inbox, potentially leading to your emails being marked as spam or even blocked entirely. It also prevents you from progressing to stricter DMARC policies like p=quarantine or p=reject, which are crucial for full protection.

Broken DMARC report indicating missing data due to incorrect 'rua' configuration.

The consequences extend beyond just missing data, they can affect your overall domain reputation and email deliverability. Without the reports to guide you, addressing issues like misconfigured SPF or DKIM records becomes a guessing game. It's a fundamental error that can prevent you from gaining the necessary insights to secure your email sending infrastructure effectively, potentially landing your legitimate emails on a blocklist or blacklist. Suped provides real-time alerts for these critical DMARC issues, ensuring you are immediately aware of any problems.

Best practices for RUA configuration

Ensuring the correct configuration of your 'rua' URI is straightforward but requires attention to detail. Always include the 'mailto:' prefix, even if you are sending reports to an external domain. The DMARC specification treats report URIs as generic URIs, with the 'mailto:' scheme specifically for email addresses.

Check syntax: Always double-check your DMARC record to ensure the 'mailto:' prefix is present. A simple typo can prevent report delivery. Use a DMARC record validator or generator to confirm accuracy.
External domains: If you are sending DMARC reports to an address on a different domain, the 'mailto:' prefix is still required. Additionally, ensure the receiving domain has published a DMARC record to authorize your domain to send reports to it, often using a specific DNS record.
Multiple addresses: You can specify multiple 'rua' URIs by separating them with commas, ensuring each URI has its own 'mailto:' prefix.

Utilizing a platform like Suped for DMARC monitoring simplifies compliance. We provide AI-powered recommendations to fix configuration issues, including correct URI formatting. Our unified platform combines DMARC, SPF, and DKIM monitoring, offering a comprehensive view of your email security and deliverability. With Suped, you get not just data, but actionable insights.

Conclusion

The 'mailto:' prefix in a DMARC 'rua' URI is a non-negotiable requirement for the successful delivery of aggregate reports. It ensures that email receivers correctly interpret the destination as an email address, allowing your domain to receive the vital data needed for email security and deliverability.

By adhering to this standard and using robust tools like Suped, you can ensure your DMARC implementation is effective, providing clear visibility into your email sending practices and protecting your brand from spoofing and phishing attacks.