Tag Archive for: SPF policy

What is SPF Email?

SPF (Sender Policy Framework) is an email authentication protocol designed to detect email spoofing and prevent unauthorized senders from sending messages on behalf of a particular domain.

SPF email records help maintain a list of verified senders for your domain that can be publicly looked up and retrieved by receiving servers to authenticate emails and are mentioned under RFC 7208.

SPF meaning in Email

SPF stands for Sender Policy Framework and was first introduced in the early 2000s. While SPF was earlier an acronym for Sender Permitted From ( also called SMTP+SPF), in February of 2004, SPF came to be known by the popular acronym that we are familiar with today, which is: Sender Policy Framework.

How does SPF work?

SPF in email works by allowing domain owners to publish a list of authorized email servers (IP addresses or hostnames) that are allowed to send emails on their behalf. Here is how SPF works step-by-step:

1. Publishing your record for SPF

The domain owner publishes an SPF record in the DNS of their domain. This record specifies which email servers are authorized to send emails to that domain.

2. Your email is received

When an email is sent, it contains information about the sender’s domain.

3. Extracting the Sender’s Domain

The recipient’s email server extracts the domain from the sender’s email address.

4. DNS lookup is performed

The recipient’s email server performs a DNS lookup to retrieve the SPF record of the sender’s domain.

5. SPF authentication is performed

The SPF record contains a policy that defines which servers are allowed to send emails for the domain. The recipient’s email server compares the IP address or hostname of the server that sent the email against the list of authorized servers specified in the SPF record.

6. Final authentication result is determined

Based on the SPF check, the recipient’s email server determines whether the email came from an authorized server or not.

7. Action is taken based on the results

The recipient’s email server takes action based on the SPF check result. It could accept the email, or even mark it as spam.

How to use SPF email?

To use the SPF email standard, you must make sure you have a proper understanding of how it works, and check your domain’s and email service provider’s SPF support. Following this, you can create a record for SPF, publish the record on your DNS, and ideally combine your SPF DNS implementation with DKIM and DMARC to prevent spoofing.

Why is Sender Policy Framework Important for Email?

SPF is important to ensure emails sent from your domain are genuine, and not fake lures created by cyberattackers to trick your customers. Here are some key benefits of SPF:

Reduced Email Spoofing

SPF helps combat email spoofing by verifying the authenticity of the sending server.

Improved Email Deliverability

Implementing SPF can enhance email deliverability rates. When recipient servers perform an SPF check and find that the sending server is authorized, they are more likely to accept the email rather than mark it as spam or reject it.

Reduced False Positives

By accurately identifying authorized email servers, SPF reduces the likelihood of legitimate emails being marked as spam. This helps prevent false positives and ensures that important emails reach the intended recipients’ inboxes.

Enhanced Sender Reputation

SPF plays a role in building and maintaining a positive sender reputation. By implementing SPF, domain owners demonstrate their commitment to email security and authentication.

Phishing and Spam Mitigation

SPF helps in reducing the effectiveness of phishing attempts and spam campaigns. SPF makes it more challenging for malicious actors to send fraudulent emails claiming to be from reputable domains.

Compliance with Email Standards

Many email service providers and organizations encourage or require the use of SPF as part of their email policies.

How to Enable SPF Policy?

To create an SPF record, you need to follow these general steps:

Determine the authorized email servers

Identify the IP addresses or hostnames of the email servers that are authorized to send emails on behalf of your domain. This may include your own organization’s email servers or third-party email service providers.

Define your SPF policy

Determine the policy for SPF. This involves specifying which servers are allowed to send emails for your domain. You can choose to either allow only specific servers or include a range of servers based on IP addresses or hostnames.

Determine SPF Format

SPF records are published as a TXT record in your domain’s DNS. The record should be in a specific format and contain the necessary information. Here’s an example of an SPF record:

Publish the SPF record

Access your domain’s DNS management system, which is typically provided by your domain registrar or hosting provider. Locate the DNS settings for your domain and add a new TXT record containing your SPF record. Specify the hostname (usually “@” for the domain itself) and paste the SPF record in the value field.

SPF Record Example

SPF record TXT in your DNS will look like this:

This record defines a set of hosts as valid senders for all messages sent through the server at 192.168.0.0/16, but it does not specify where those messages will be delivered—they could be delivered locally or they could be delivered by another server on the Internet, depending on how the other servers are configured in the email infrastructure (which we’ll get into later).

How to Check SPF?

Once you’ve added the SPF record, it may take some time for the changes to propagate across the DNS system. Use our SPF record check tool to verify the correctness of your record and ensure it is being recognized by the DNS.

It’s important to note that SPF records can be complex, depending on the specific requirements of your email infrastructure. If you’re unsure about the syntax or need more advanced configurations, it’s recommended to consult your system administrator or IT support for assistance in creating the SPF record correctly.

SPF for Third-Party Vendors

What is SPF for your third-party vendors? To align your third parties for SPF, you need to include IP addresses or SPF-handling domains unique to them in your domain’s record. But beware, do not include multiple SPF records for the same domain!

For example, if you are using SuperEmails.net as your email sender, and their SPF-handling domain is spf.superemails.net, your SPF record might be:

v=spf1 include:spf.superemails.net -all

We have got you covered. Our knowledge contains a list of famous third-party email vendors with specific instructions on how to configure the protocol for each of them.

What are the Limitations of SPF?

While SPF does protect your domain against spam and forged sender addresses, it is not all perfect! Here’s why:

SPF can encounter challenges with email forwarding. When an email is forwarded from one server to another, the original SPF authentication may fail because the forwarding server is not listed in the SPF record of the sender’s domain.
As the number of authorized email servers and third-party services increases, the complexity of managing and maintaining SPF records grows.
SPF focuses solely on verifying the authenticity of the sending server and does not provide encryption or content verification as DKIM does.
SPF does not provide visibility into the specific sender of an email. It only validates the authenticity of the sending server. Therefore it becomes crucial to pair SPF with DMARC.

Make SPF Even Better With PowerDMARC

SPF by itself is still effective, but cybercriminals have come up with ways to bypass the IP address verification phase. But SPF technology is made relevant again by incorporating it into DMARC.

We pair SPF with DKIM and DMARC

Along with aligning DMARC against both SPF and DKIM, PowerDMARC takes this one step further with AI-based real-time threat modeling that uncovers spoofing attacks around the globe.

Reporting and Feedback

Neither SPF nor DKIM gives the domain owner feedback about emails that fail authentication. DMARC sends detailed DMARC reports directly to you, which the PowerDMARC app converts into easy-to-read charts and tables. Using the analytics data, you can change your email marketing strategy on the fly.

Control What Happens to Unauthenticated Email

DMARC lets you decide whether an email that fails validation goes to inbox, spam, or gets rejected. With PowerDMARC, all you have to do is click one button to set your DMARC policy. It’s that easy.

July 1, 2023/by Ahona Rudra

SPF Policy for Email Senders

Blogs

The fight against spam and email fraud is never-ending, and as a result, various industry standards have emerged to help stem the flood. One of such standards is the SPF (“Sender Policy Framework”) record, which allows a domain to specify which servers may send emails on its behalf.

Read an excerpt from RFC 7208.

To use an SPF record, you don’t need to grasp every detail, but having a better understanding can help you see the big picture.

Let’s look at how you may boost email deliverability and protect your domain’s reputation with SPF policy.

What Is an SPF Policy?

SPF, or Sender Policy Framework, is a method for verifying the legitimacy of an email sender. SPF can prevent spammers from sending spam or phishing emails from using your domain. It’s also an anti-phishing tool that helps fight fraudulent emails that appear to come from legitimate sources.

An SPF policy is a list of mail servers authorized to send messages on behalf of your domain. When someone tries to send you an email, their server checks the SPF record for your domain and determines if it should accept the message or not.

What Is an SPF Policy Record?

An SPF record is a TXT record that defines which servers are allowed to send emails on behalf of your domain name. If someone tries to send an email from one of these servers but doesn’t pass this test, they will not receive an email from us because they do not have permission to send it on behalf of your domain name.

How Does SPF Policy Work?

SPF Policy is a service that helps you prevent email spoofing. Its API allows you to verify email senders and ensure your mail servers are not being used for phishing or spam.

It is a framework that allows you to configure your domain’s SPF, DKIM and DMARC records.

The following steps describe how it works:

You create an SPF record, which tells other mail servers which servers are allowed to send mail from your domain. This prevents people from sending fraudulent emails using your domain in their message’s “From” field.
You create a DKIM record, which adds a digital signature to every message sent from your domain so that recipients can verify that messages claiming to be from you come from you. When someone sends an email using your domain’s identity, the recipient can check the digital signature against public key hashes stored in its email system. This ensures that only authorized users can send messages on behalf of your domain and helps prevent spoofing attacks where someone impersonates another user’s identity by sending messages with forged headers claiming to be from them.

What Are the Benefits of Implementing an SPF Policy?

1. Improves Deliverability

If your SPF record is properly configured, it will greatly reduce the chances of spam complaints from recipients or spam filters.

2. Improves Domain Reputation

Use SPF to specify which servers are allowed to send an email on behalf of your domain. Anyone who receives an email claiming to be from your company can check the sender’s IP address against the SPF policy in the message header. If there’s no match, they’ll know that it didn’t come from you. If someone attempts to impersonate you by sending spoofed messages with forged headers, their efforts won’t be successful if your domain has a valid SPF record.

3. Reduces Spam Complaints

By using SPF, legitimate emails from your users will reach their destination inboxes more reliably, which reduces the number of spam complaints that your company receives.

4. Protects Against Phishing Attacks

Phishing attacks rely on spoofed email addresses to trick people into clicking on links or downloading malware. By using SPF (or another method), you can inform recipients that they should only trust emails coming from authorized sources.

5. Combat Email Spoofing

With SPF, you can prevent your emails from being sent from unauthorized sources. This helps protect your brand’s reputation, especially if a malicious party sends out a phishing email with your company’s logo or name in it.

6. Reduce Bounce Rate

An SPF policy will help you avoid sending emails to blocked domains and prevent bounce rates from going up due to spam filtering issues.

How Do You Create an SPF Policy?

SPF records are stored in DNS (Domain Name System) records, which email systems use to map domain names to IP addresses such as 192.0.2.1 that identify servers within the domain.

Here’s how you create an SPF policy:

Gather IP addresses used to send an email.
Make a list of your sending domains.
Create the a free policy in your DNS record with the help of our SPF record generator tool.

What Should You Consider When Creating an SPF Policy?

SPF policies are a great way to protect your brand. But what should you consider when creating an SPF policy?

The following guidelines can help you build a solid policy:

1. Have a complete list of all your email senders included in your DNS’s SPF record policy

This is the most important aspect of an SPF record. If you don’t have every email sender listed, then you’re not going to be able to prevent spoofing attacks. This means that if you have a third party sending on behalf of your company or an employee sending from their personal account, then those emails should be included in the SPF policy.

2. Make sure your TXT record is under the 10 DNS lookup limit

Too many DNS lookups for SPF is a problem since it allows only up to 10. Organizations operating through various third-party vendors run the risk of exceeding this limit quite easily and failing SPF for authentic emails.

An SPF flattening tool makes it possible to combine multiple DNS lookup requests into one request, which means you can get more done with fewer requests.

3. Make sure your TXT record is within the 255 character SPF length limit

This means that all of the text in one line must fit within 255 characters without adding spaces between words or punctuation marks (like periods). This allows ISPs to process records more quickly and efficiently. Exceeding the SPF string character limit also breaks SPF and invalidates your record.

Conclusion

Ultimately, the SPF policy is an added layer of protection for organizations, encouraging others to verify and trust your domain. In the long run, this will be beneficial to both your brand and the success of your email marketing efforts. It’s not something that you need to implement right away, but it should be part of a long-term email strategy.

May 17, 2022/by Ahona Rudra