Understanding the realities and limitations of the Sender Policy Framework (SPF) is crucial for making informed decisions about your email security. Believing in SPF myths can lead to a false sense of security, potentially putting your system at risk. For example, the misconception that SPF is self-sufficient could lead to a lack of additional security measures, making your system vulnerable to attacks.
So, here we have listed out 7 misconceptions along with explanations as to why they aren’t true or correct.
MYTH 1: SPF Prevents All Types of Email Spoofing
SPF can only save you from attacks attempted by spoofing the envelope sender address and not the ‘From’ header seen by email recipients. That’s exactly why SPF should be paired up with DKIM and DMARC. DKIM ensures nobody tampers with email content in transit, while DMARC instructs recipients’ mail servers on how to deal with illegitimate emails sent from your domain.
MYTH 2: SPF is a One-Time Job
Creating an SPF record is just the beginning. To ensure the ongoing effectiveness of your email security, it’s crucial to regularly update your SPF record with all the IP addresses used to send emails on your behalf. Additionally, maintaining the syntax and other configurations is essential for accuracy and effectiveness.
MYTH 3: SPF Records Can be Unlimited in Length
Each SPF record string is limited to 255 characters. Exceeding this limit results in parsing issues and DNS lookup failures, ultimately disrupting the email delivery and authentication processes. This limit is imposed to avoid DNS query overhead, network latency, excess resource consumption, and DDoS attacks.
If you exceed this limit, try fixing it by removing unnecessary mechanisms and modifiers. Also, use SPF macros to dynamically add information to your SPF record.
MYTH 4: Only Large Organizations Need SPF
Nobody is safe from threat actors; even small businesses are vulnerable today! So, it doesn’t matter if thousands of people send emails using your domain or only a few. If you have a domain, then it definitely has the possibility of coming under the radar of cybercriminals.
However, the way a small and a large company will have to manage their respective SPF records differs. Due to simpler email infrastructure and fewer sending sources, a small company’s SPF record will be good to go with a basic setup and won’t require frequent updates as there will be stability. But, if we talk about a large company, its email infrastructure will be extensive, complex, and dynamic, hence requiring more attention, an advanced setup, and services like SPF flattening.
MYTH 5: SPF Covers All Mail Servers Automatically
Each mail server or service that sends emails on behalf of your domain must be explicitly listed in the SPF record. This inclusion is done using mechanisms like ip4, ip6, include, and a. This means if your domain uses multiple services (e.g., Google Workspace, a marketing platform like Mailchimp, and a transactional email service like SendGrid), you need to include each of these in your SPF record.
MYTH 6: SPF Only Benefits the Sender
While SPF primarily protects the sender’s domain, it also helps recipients by reducing the likelihood of receiving spoofed emails, contributing to overall email ecosystem security.
MYTH 7: SPF Validation Slows Down Email Delivery
This isn’t true; SPF is developed and updated to make emailing not just a secure but efficient process. Proper configuration, optimization of DNS infrastructure, and regular maintenance ensure that SPF validation is performed quickly and effectively, allowing emails to be delivered promptly without noticeable delays.
Image sourced from esecurityplanet.com
Final Words
By understanding and addressing these myths, organizations can confidently implement SPF to enhance their email security without worrying about adverse effects on email delivery performance. But, of course, all this can be overwhelming and daunting, especially if you don’t have an expert onboard. But with AutoSPF, we can render all your SPF-related worries. Are you interested in knowing more? Get in touch.
