What is TLS-RPT? A detailed guide

What is TLS-RPT? Transport Layer Security Reporting (TLS-RPT) is a foundational element of secure email communication. Understanding TLS-RPT is essential for safeguarding your organization’s email and maintaining its reputation.

Below, we explain what TLS-RPT is, outline its purpose, and show how it supports broader email authentication protocols.

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What is TLS-RPT, and what does it do?

TLS-RPT explained

So, what is TLS-RPT? TLS-RPT is an email security standard that enables domain owners to receive reports about encrypted email delivery failures. These failures happen when external servers attempt to receive messages using TLS encryption, but the process encounters issues.

TLS-RPT definition

TLS-RPT is a reporting mechanism that provides visibility into issues that happen during the TLS process. These reports are sent automatically to domain owners, helping to identify, diagnose, and resolve encryption problems that might otherwise go unnoticed. This allows organizations to proactively protect their recipients from potential cyberthreats such as Man-in-the-Middle (MitM) attacks.

What is TLS-RPT, and why does email transmission matter?

Email is vital to business communication and a frequent target for cybercriminals. Without secure transmission, emails containing sensitive information can be intercepted during transit.

Real-world example:

Consider that financial or legal documents are emailed to a client. If the email isn’t encrypted, it could be intercepted during transmission, leading to:

A data breach
Legal liability
Loss of customer trust

The role of TLS in email security

What is TLS-RPT’s role? TLS encrypts data sent between email servers, ensuring that messages remain private while in transit. When both the sender and recipient servers support TLS, the email content is protected from unauthorized access.

But TLS encryption depends on its configuration. If misconfigured or if a threat actor attempts to downgrade the connection to bypass encryption, emails can be accessed. TLS-RPT detects these issues, allowing for timely correction.

Consequences of not using TLS-RPT

Businesses that don’t implement TLS-RPT risk the following:

Undetected encryption failures: Issues with TLS might go unnoticed, leaving emails vulnerable
Increased risk of data breaches: Sensitive information could be accessed during transmission
Damage to brand reputation: A lack of proper email security can lead to the loss of customer trust
Compliance risks: Regulations such as the General Data Protection Regulation (GDPR) require secure email transmission

What is TLS-RPT, and how does it work?

TLS-RPT works alongside other email security protocols to give domain owners visibility into encryption issues during email transmission. By identifying failed security connections, TLS-RPT helps companies maintain email integrity and compliance.

Key terms to know:

TLS: Encrypts email in transit between email servers to prevent interception
Mail Transfer Agent Strict Transport Security (MTA-STS): Able to instruct sending servers to only deliver emails via encrypted connections

What is TLS-RPT’s process?

Your organization attempts to deliver an email to a recipient
If the connection fails to use TLS encryption, the receiving server generates a report
This report is sent to an email address specified in the domain’s DNS record
Your business receives regular reports outlining encryption-related issues
Your company’s security or IT team analyzes these reports to identify, investigate, and resolve any problems

What is in a TLS-RPT report?

A standard TLS-RPT report includes the following information:

The IP addresses involved
The type of issue
The TLS policy
The date and time of the issue

These reports are commonly delivered in JSON format.

What is TLS-RPT, and what are its benefits?

Implementing TLS-RPT provides advantages to organizations of all sizes. Businesses that adopt TLS-RPT can:

Detect security issues early

TLS-RPT alerts companies when there are problems with encrypted email delivery. This enables fast identification of misconfigurations or potential cyberattacks, reducing vulnerability.

Improve email security

By identifying encryption failures, TLS-RPT checks that all outgoing emails are transmitted securely. This lowers the risk of data breaches and interception by cybercriminals.

Enhance regulatory compliance

Industries such as finance, healthcare, and legal services are subject to strict regulations on data protection. TLS-RPT helps meet compliance requirements by providing documentation of encryption issues.

Build customer trust

Customers expect their information to be securely handled. Using TLS-RPT shows a commitment to email security, enhancing your organization’s credibility and reputation.

Solve problems proactively

TLS-RPT provides security and IT teams with the data needed to identify and resolve issues before they escalate.

Discover how TLS-RPT can strengthen email security.

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What is TLS-RPT, and who uses it?

TLS-RPT is valuable across multiple roles:

Small business owners: Gain visibility into email security even without a full-time security or IT team, protecting customer data and brand reputation
Marketing professionals: Ensure marketing emails are securely delivered to clients
IT and security teams: Access detailed reports that support fast diagnosis and solving of TLS-related failures

When to implement TLS-RPT

TLS-RPT should be implemented:

When monitoring email transmission proactively is a priority
As part of a broader email authentication strategy, alongside Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting, and Conformance (DMARC)
When enforcing encrypted email delivery through MTA-STS

What is TLS-RPT: FAQs

What does TLS stand for?

TLS stands for Transport Layer Security, which is a standard that encrypts data sent over the internet. TLS is commonly used to secure email communications and protect messages from interception during transmission.

How can I set up TLS-RPT?

To set up TLS-RPT, follow these three main steps:

Choose an email address to receive reports: This should be a monitored address that’s regularly checked.
Publish a TLS-RPT record in the DNS: Add a TXT record that specifies where reports should be sent. For example:

Host	Type	Value
_smtp._tls.yourdomain.com	TXT	`v=TLSRPTv1; rua=mailto:[email protected]`

Review and act on the reports: Analyze the incoming TLS-RPT reports and resolve any issues with your company’s security or IT team.

What is a TLS report?

A TLS report is a document, typically JSON formatted, that’s sent by external email servers to your organization. It outlines encryption-related issues seen during email delivery.

How does TLS-RPT relate to DMARC and MTA-STS?

TLS-RPT works with DMARC and MTA-STS:

DMARC helps prevent spoofing and phishing emails by authenticating the sender and message content.
MTA-STS enforces TLS encryption for email delivery; with the correct policy, it ensures that messages are only transmitted over secure channels.
TLS-RPT provides visibility into encryption issues, complementing DMARC and MTA-STS as part of a comprehensive email security strategy.

What happens if I don’t use TLS-RPT?

If TLS-RPT isn’t implemented, your business will lack visibility into whether outgoing emails are being securely delivered using TLS encryption. This can result in undetected encryption failures, increased risk of data breaches, and damage to your company’s reputation.

Have more questions or want to see TLS-RPT in action?

Book a demo with Sendmarc and let our experts show your organization how easy it is to secure its emails.