Understanding DMARC reporting behavior in Avanan protected mail flow
One of the more confusing situations organizations encounter after deploying Avanan is a sudden increase in DMARC failures appearing in their aggregate reports. In many cases, these failures are associated with hostnames such as cloud-sec-av.com and can involve large volumes of mail from legitimate senders that have been operating successfully for years.
At first glance, the reports can be alarming. SPF may show failures, DKIM may appear broken, and DMARC compliance percentages can drop unexpectedly. For organizations actively monitoring their email authentication posture, the data often suggests that a significant problem has emerged. The confusing part is that nothing appears to be wrong. Users continue receiving messages normally, trusted services continue sending mail successfully, and no widespread delivery issues are reported.
This raises an important questions: If DMARC is reporting failures, why is everything still working?
What We Started Seeing in DMARC Reports
A common pattern begins shortly after Avanan is deployed. Organizations that previously had clean DMARC reporting suddenly begin seeing traffic associated with Avanan infrastructure. Hostnames such as us.cloud-sec-av.com appear in aggregate reports, often accompanied by SPF failures, DKIM failures, and low DMARC compliance percentages.
The immediate assumption is usually the authentication configuration has changed or that a previously authorized sender has become misconfigured. However, further investigation often reveals the affected messages are being delivered successfully and originate from legitimate email services that have not changed their configuration.
At this point, the investigation shifts from identifying a broken sender to understanding why the reporting data no longer matches what administrators expect to see.
What DMARC Reports Are Really Telling Us
One of the most common misconceptions about DMARC reporting is that it tells the complete story of a message's journey from sender to recipient. In reality, DMARC reports only describe what a reporting organization observed when it evaluated a message. They do not preserve the full authentication history of every system that handled the email before it arrived.
This distinction is important because modern email rarely travels directly from the sender to the recipient. Messages frequently pass through multiple systems responsible for security inspection, threat detection, routing, archiving, and policy enforcement. Each of these systems can become part of the message path and influence what downstream systems observe during authentication checks.
As a result, the authentication results recorded in a DMARC report may not always reflect the original authentication state of the message when it first left the sender.
The Role Avanan Plays in the Mail Flow
To understand why these failures appear, it is important to understand Avanan's role in the mail flow.
Avanan is not simply a reporting or monitoring solution. To provide phishing protection, malware detection, link analysis, and remediation capabilities, Avanan participates directly in the processing of email messages. Messages are analyzed before being delivered to the recipient, allowing Avanan to inspect content and apply security controls before users interact with the email.
Because Avanan becomes part of the delivery path, downstream systems may observe Avanan infrastructure during messages processing. This is often why organizations begin seeing hostnames associated with Avanan appear in their DMARC reports shortly after deployment.
The presence of Avanan infrastructure in reporting does not necessarily indicate a problem. Rather, it reflects the fact that Avanan has become part of the message's journey from sender to recipient.
Example: Following a Message Through Avanan
Let's look at a simplified example of a message being sent from a trusted email service.
Imagine Constant Contact sends an email campaign on behalf of an organization. The message leaves Constant Contact with valid SPF and DKIM authentication and begins its journey toward the recipient. Microsoft 365 initially evaluates the message and confirms that SPF, DKIM, and DMARC all pass successfully.
Before the message reaches the recipient, Avanan performs its security inspection. During the process, Avanan analyzes the message from phishing attempts, malware, malicious links, impersonation attacks, and other threats. Once the inspection is complete, the message continues through the environment and is ultimately delivered to the user's mailbox.
At the same time, DMARC reporting systems only record what they observe at the specific point in the message's journey. Because Avanan has become part of the mail flow, the infrastructure observed during reporting may differ from the original sender's infrastructure. This can result in SPF, DKIM, and DMARC failures appearing in reports even though the original message was legitimate and successfully delivered.
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The important takeaway is that the message itself was never necessarily unauthenticated. The authentication results recorded in the DMARC reports represent what was observed at a particular stage of processing, not necessarily the complete authentication history of the message from sender to recipient.
Why Legitimate Email Can Look Like a DMARC Failure
Email authentication is evaluated at the point where a message is observed. When intermediary systems participate in the message processing, the authentication results records later in the delivery process may differ from those observed earlier.
This can create situations where a legitimate sender successfully transmits a message, the message passes through Avana for inspection, and the message is ultimately delivered without issue. Yet the resulting DMARC reports still record SPF, DKIM, or DMARC failures. The report is not necessarily identifying a malicious message or a configuration problem. Instead, it is documenting the authentication state observed at the specific state of processing.
For administrators reviewing aggregate reports, this can appear as a false positive because the reported failures does not correspond to any actual delivery issue or security event. The message itself was legitimate and successfully delivered, but the authentication result observed by the reporting organization may differ from those that existed earlier in the message's journey.
Identifying Expected Behavior vs. Actual Authentication Issues
The key difference between a reporting anomaly and a genuine authentication problem is the overall context. When messages are being delivered successfully, the reported traffic can be traced to known Avanan infrastructure and there is no evidence of spoofing or abuse, the DMARC failures are often the result of how the message was processed and observed rather than a problem requiring remediation.
This does not mean DMARC reporting is incorrect. The reporting organization is accurately documenting what it observed. However, without understanding the role intermediary security platforms play in modern email delivery, it is easy to misinterpret those observations as evidence of a security issue.
When reviewing these report entries it is important to evaluate the complete picture rather than focusing solely on the authentication result. Message delivery, sender legitimacy, infrastructure ownership, and user impact should all be considered before concluding that a security problem exists.
Key Takeaways
DMARC reports remain one of the most valuable tools available for monitoring email authentication, but they are most effective when interpreted within the context of the entire mail flow. When Avanan is deployed, it becomes part of that flow and can influence what downstream systems observe during authentication evaluation.
As a result, organizations may encounter DMARC failures associated with Avanan infrastructure even when the original messages are legitimate, properly authenticated, and delivered successfully. Understanding the relationship allows administrators to distinguish genuine authentication issues from reporting anomalies and focus their attention on threats that require action.
In the cases investigated, the appearance of Avanan related failures in DMARC reports was not the result of spoofing, unauthorized senders, or a misconfigured DMARC policy. Instead, it was a byproduct of how modern email security platforms participate in the message delivery process and how DMARC reporting captures authentication results at specific points along the journey.
One of the more confusing situations organizations encounter after deploying Avanan is a sudden increase in DMARC failures appearing in their aggregate reports. In many cases, these failures are associated with hostnames such as cloud-sec-av.com and can involve large volumes of mail from legitimate senders that have been operating successfully for years.
At first glance, the reports can be alarming. SPF may show failures, DKIM may appear broken, and DMARC compliance percentages can drop unexpectedly. For organizations actively monitoring their email authentication posture, the data often suggests that a significant problem has emerged. The confusing part is that nothing appears to be wrong. Users continue receiving messages normally, trusted services continue sending mail successfully, and no widespread delivery issues are reported.
This raises an important questions: If DMARC is reporting failures, why is everything still working?
What We Started Seeing in DMARC Reports
A common pattern begins shortly after Avanan is deployed. Organizations that previously had clean DMARC reporting suddenly begin seeing traffic associated with Avanan infrastructure. Hostnames such as us.cloud-sec-av.com appear in aggregate reports, often accompanied by SPF failures, DKIM failures, and low DMARC compliance percentages.
The immediate assumption is usually the authentication configuration has changed or that a previously authorized sender has become misconfigured. However, further investigation often reveals the affected messages are being delivered successfully and originate from legitimate email services that have not changed their configuration.
At this point, the investigation shifts from identifying a broken sender to understanding why the reporting data no longer matches what administrators expect to see.
What DMARC Reports Are Really Telling Us
One of the most common misconceptions about DMARC reporting is that it tells the complete story of a message's journey from sender to recipient. In reality, DMARC reports only describe what a reporting organization observed when it evaluated a message. They do not preserve the full authentication history of every system that handled the email before it arrived.
This distinction is important because modern email rarely travels directly from the sender to the recipient. Messages frequently pass through multiple systems responsible for security inspection, threat detection, routing, archiving, and policy enforcement. Each of these systems can become part of the message path and influence what downstream systems observe during authentication checks.
As a result, the authentication results recorded in a DMARC report may not always reflect the original authentication state of the message when it first left the sender.
The Role Avanan Plays in the Mail Flow
To understand why these failures appear, it is important to understand Avanan's role in the mail flow.
Avanan is not simply a reporting or monitoring solution. To provide phishing protection, malware detection, link analysis, and remediation capabilities, Avanan participates directly in the processing of email messages. Messages are analyzed before being delivered to the recipient, allowing Avanan to inspect content and apply security controls before users interact with the email.
Because Avanan becomes part of the delivery path, downstream systems may observe Avanan infrastructure during messages processing. This is often why organizations begin seeing hostnames associated with Avanan appear in their DMARC reports shortly after deployment.
The presence of Avanan infrastructure in reporting does not necessarily indicate a problem. Rather, it reflects the fact that Avanan has become part of the message's journey from sender to recipient.
Example: Following a Message Through Avanan
Let's look at a simplified example of a message being sent from a trusted email service.
Imagine Constant Contact sends an email campaign on behalf of an organization. The message leaves Constant Contact with valid SPF and DKIM authentication and begins its journey toward the recipient. Microsoft 365 initially evaluates the message and confirms that SPF, DKIM, and DMARC all pass successfully.
Before the message reaches the recipient, Avanan performs its security inspection. During the process, Avanan analyzes the message from phishing attempts, malware, malicious links, impersonation attacks, and other threats. Once the inspection is complete, the message continues through the environment and is ultimately delivered to the user's mailbox.
At the same time, DMARC reporting systems only record what they observe at the specific point in the message's journey. Because Avanan has become part of the mail flow, the infrastructure observed during reporting may differ from the original sender's infrastructure. This can result in SPF, DKIM, and DMARC failures appearing in reports even though the original message was legitimate and successfully delivered.
The important takeaway is that the message itself was never necessarily unauthenticated. The authentication results recorded in the DMARC reports represent what was observed at a particular stage of processing, not necessarily the complete authentication history of the message from sender to recipient.
Why Legitimate Email Can Look Like a DMARC Failure
Email authentication is evaluated at the point where a message is observed. When intermediary systems participate in the message processing, the authentication results records later in the delivery process may differ from those observed earlier.
This can create situations where a legitimate sender successfully transmits a message, the message passes through Avana for inspection, and the message is ultimately delivered without issue. Yet the resulting DMARC reports still record SPF, DKIM, or DMARC failures. The report is not necessarily identifying a malicious message or a configuration problem. Instead, it is documenting the authentication state observed at the specific state of processing.
For administrators reviewing aggregate reports, this can appear as a false positive because the reported failures does not correspond to any actual delivery issue or security event. The message itself was legitimate and successfully delivered, but the authentication result observed by the reporting organization may differ from those that existed earlier in the message's journey.
Identifying Expected Behavior vs. Actual Authentication Issues
The key difference between a reporting anomaly and a genuine authentication problem is the overall context. When messages are being delivered successfully, the reported traffic can be traced to known Avanan infrastructure and there is no evidence of spoofing or abuse, the DMARC failures are often the result of how the message was processed and observed rather than a problem requiring remediation.
This does not mean DMARC reporting is incorrect. The reporting organization is accurately documenting what it observed. However, without understanding the role intermediary security platforms play in modern email delivery, it is easy to misinterpret those observations as evidence of a security issue.
When reviewing these report entries it is important to evaluate the complete picture rather than focusing solely on the authentication result. Message delivery, sender legitimacy, infrastructure ownership, and user impact should all be considered before concluding that a security problem exists.
Key Takeaways
DMARC reports remain one of the most valuable tools available for monitoring email authentication, but they are most effective when interpreted within the context of the entire mail flow. When Avanan is deployed, it becomes part of that flow and can influence what downstream systems observe during authentication evaluation.
As a result, organizations may encounter DMARC failures associated with Avanan infrastructure even when the original messages are legitimate, properly authenticated, and delivered successfully. Understanding the relationship allows administrators to distinguish genuine authentication issues from reporting anomalies and focus their attention on threats that require action.
In the cases investigated, the appearance of Avanan related failures in DMARC reports was not the result of spoofing, unauthorized senders, or a misconfigured DMARC policy. Instead, it was a byproduct of how modern email security platforms participate in the message delivery process and how DMARC reporting captures authentication results at specific points along the journey.