Understanding ARC validation to strengthen email

Today, email security has become a paramount concern. The constant evolution of cyber threats demands innovative and robust solutions. With recent enhancements in email security by tech giants like Google, the need to adapt and adopt these new measures has become more critical than ever.

In this context, ARC validation (Authenticated Received Chain) emerges as a key solution to address specific challenges related to the authentication of forwarded emails, an area that had previously shown notable vulnerabilities.

By taking a detailed look at the recent security improvements implemented and ARC’s critical role in this evolving ecosystem, we aim to provide a comprehensive perspective on the importance of adopting these measures to ensure secure and verifiable communication in the digital age.

Lately, major email service providers have implemented a series of security enhancements to combat fraud and abuse. These improvements include more sophisticated algorithms for spam and phishing detection, stricter enforcement of email authentication policies, and the use of artificial intelligence to identify anomalous behavior patterns, among others.

Faced with this scenario, at cdmon, we have adopted a proactive stance by rigorously implementing security protocols such as SPF, DKIM, and DMARC. These protocols are effective in validating the authenticity of messages, but face challenges in scenarios like mail forwarding. This is because authenticity can be compromised, making it difficult to verify the legitimacy of the emails by the final recipients.

In this context, ARC validation stands out as an important advancement. ARC validation allows servers to «remember» the authenticity of a message throughout its journey. ARC headers create a chain of trust, facilitating service providers to verify the authenticity of emails. This way, the secure delivery of legitimate emails is ensured, reducing false positives.

ARC does not replace SPF, DKIM, and DMARC protocols but complements them. SPF and DKIM provide mechanisms to verify the sender and the integrity of the message. DMARC specifies how messages that fail these verifications should be treated. Finally, ARC ensures that this authenticity information is preserved through multiple intermediaries.

ARC validation, or Authenticated Received Chain, is a security standard for email. It has been designed to preserve and validate the authentication information of messages as they pass through different mail servers. This is especially important in forwarding situations.

ARC is introduced as a solution that allows intermediaries (such as mail forwarding services or mailing lists) to digitally sign the headers and authenticity verifications of messages, creating an «authentication chain» that accompanies the email throughout its journey.

ARC validation works by creating a series of headers that are added to outgoing email messages. Each contains critical information about the message’s authenticity throughout its trajectory. These headers allow each intermediary in the delivery chain to add details about the SPF, DKIM, and DMARC verifications carried out at each step of the way without altering the information provided by previous intermediaries, maintaining the original message’s authenticity proof, even after multiple forwardings.

ARC’s ability to maintain the authenticity of a message through multiple forwardings makes it an invaluable tool in the fight against phishing and other forms of email abuse, ensuring that recipients can trust the legitimacy of the messages they receive, regardless of their route through the network.

As we move forward in the digital era, email security remains a key battleground against cyber threats. ARC validation, together with protocols like SPF, DKIM, and DMARC, has laid the groundwork for a more secure and reliable email.

However, the cybersecurity landscape is dynamic, with attackers constantly evolving and adapting their tactics. In this context, continuous adaptation and innovation in email security strategies are crucial.

To maximize its impact on improving email security, it is vital that ARC be widely adopted by email service providers, businesses, and organizations of all sizes. This requires not only the availability of tools and resources to facilitate ARC’s implementation, but also ongoing efforts to educate system administrators and security professionals about ARC’s benefits and how to implement it correctly.

The future of email security with ARC is promising but requires an ongoing commitment to innovation, collaboration, and education. As we face emerging challenges and seize the opportunities new technologies offer, the evolution of ARC and other security protocols will be fundamental to ensuring the integrity and trust in our digital communications.

With the collaboration of all actors in the email ecosystem, we can move towards a future where email security is more robust, resilient, and tailored to the needs of the constantly changing digital world.