" DMARC Archives - LuxSci

Posts Tagged ‘DMARC’

Zero Trust Email

Tuesday, July 20th, 2021

Our third article on Zero Trust Architecture covers zero trust email and the systems it requires. In May, the Biden Administration announced a new approach to cybersecurity that included a push toward Zero Trust Architecture. We have already covered Zero Trust Architecture as a whole, and also talked about how dedicated servers are important parts of the zero trust model. Now, it’s time to talk about zero trust email.

zero trust email

Zero Trust Email and Encryption

As we discussed in our previous articles, Zero Trust Architecture begins with the presumption that an organization’s network may not be secure. Because attackers may already be inside the network, NIST stipulates that:

“…communication should be done in the most secure manner available… This entails actions such as authenticating all connections and encrypting all traffic.”

This means that emails always need encryption. While many organizations recognize external threats and encrypt their sensitive external communications, it’s still common for workplaces to use unencrypted communication methods within the company network. This is generally done under the outdated assumption that the internal network is secure.

Zero Trust Architecture understands that any attacker within the network could easily read these communications. This is why zero trust email needs to be encrypted, even when it’s within an organization’s private network. One step in this direction is to force TLS for email encryption for all entities.

The zero trust model also requires encryption at rest, so emails also need to be protected in storage, not just in transmission.

Authentication and Zero Trust Email

NIST’s publication on Zero Trust Architecture also stipulates that:

“Access to individual enterprise resources is granted on a per-session basis. Trust in the requester is evaluated before the access is granted. Access should also be granted with the least privileges needed to complete the task.”

When it comes to zero trust email, this means that sensitive messages require authentication and authorization to be read. TLS encryption alone is not sufficient, because it doesn’t have the full capability for this type of verification. While it does allow authentication and authorization on the recipient’s email account, it cannot do so on the raw message data.

LuxSci supports:

  • Sender Policy Framework (SPF) – This is a system for email authentication that can detect forged sender addresses. Due to its limitations, it is best to complement it with other email authentication measures.
  • DomainKeys Identified Mail (DKIM) – This authentication method can detect email spam and phishing by looking for forged sender addresses.
  • Domain-based Message Authentication Reporting and Conformance (DMARC) – This email authentication protocol complements SPF, allowing it to detect email spoofing. It helps to protect organizations from phishing, business email compromise attacks, and other threats that are initiated via email.

Each of these email authentication measures are useful for verifying sender identities. LuxSci also offers premium email filtering, and together these techniques limit the trust that is applied to inbound messages.

Together, these techniques identify legitimate email messages while filtering out those that are unwanted or malicious. While it isn’t directly stated in the NIST guidelines, SPF, DKIM and DMARC can all be integral parts of the zero trust framework.

Access Control and Zero Trust Email

In addition to measures for encrypting messages and verifying inbound emails, zero trust email requires granular access controls to keep out intruders. LuxSci’s Secure Email Services include a wide range of access controls that limit unauthorized access while still making the necessary resources available. These include:

  • Two-factor authentication
  • Application-specific passwords
  • Time-based logins
  • IP-based access controls
  • APIs that can be restricted to the minimum needed functionality

These configuration options help reduce the likelihood that a malicious actor can access your systems. They also limit the sensitive email data that an attacker may have access to if they do manage to compromise an organization’s network.

LuxSci’s Zero Trust Email

As a specialist provider in secure and compliant services, LuxSci’s offerings are well-positioned as zero trust email solutions. Our Secure Email aligns with Zero Trust Architecture for every industry vertical, not just HIPAA. Contact our team to find out how LuxSci can help secure your organization with a zero trust approach.

ARC and SMTP MTA-STS: The State of Domain-based Email Authentication – Part 3

Tuesday, September 19th, 2017

We’ll close (for now) our three part series on the state of domain-based authentication for emails by completing the story on technologies being deployed or defined to improve the security of the email ecosystem. In Part 1, we wrote about using Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) to authenticate the sending mail server. Part 2 described how Domain-based Message Authentication, Reporting and Conformance (DMARC) is used to provide clear guidelines for the treatment of mail that fail SPF and/or DKIM authentication.

In this post, we’ll touch on two topics that are mature works in progress in the IETF, the technical standardization organization that has brought us so much of the protocols that govern the internet. The first technology is Authenticated Received Chain (ARC), defined to handle the shortcomings of SPF and DKIM when used with mail forwarders or mailing lists. The second technology is about correcting the lack of security between Message Transfer Agents (MTA), and a solution to enforce strict transport layer security for SMTP message transfer between MTAs.

It’s worth reiterating again that all these technologies are building blocks, and only when used and deployed collectively by the entire ecosystem can we hope to create the barriers needed to thwart fake emails and mail surveillance by malicious actors.

Read the rest of this post »

DMARC: The State of Domain-based Email Authentication – Part 2

Monday, September 11th, 2017

Building a safer email ecosystem with DMARC

In our previous post, we described two techniques for authenticating an email sender:

  • Sender Policy Framework (SPF), IETF RFC 7208, which verifies if the sending MTA is indeed authorized to send mail on behalf of a domain; and
  • DomainKeys Identified Mail (DKIM), IETF RFC 6376, where a domain shows “ownership” of a mail it sends by signing portions of it so that critical aspects cannot be forged by intermediaries.

Like most technologies, these are just individual weapons in the arsenal for fighting phishing and spam. Weapons, like all tools, need to be properly used if they are to be effective. Unfortunately, as we described in the earlier post, both SPF and DKIM are deployed in a manner that reduces their usefulness. With SPF, the validation policy set by the sender is often chosen in a manner that leaves handling authentication failures at the discretion of the recipient. DKIM, on the other hand, does not even have an explicit policy directive set by the sender. Moreover, in a heterogeneous mail environment, some perfectly legitimate MTAs might not be capable of signing messages.

Building a safer email system with DMARC

Thus, receivers in actual deployments tend to “soft fail” any SPF and/or DKIM validation failures as there are reasonable situations when legitimate mail can fail such checks. A common example is forwarded mail (which fails SPF), or mail sent via a mailing list (which fails DKIM). Mail providers consider it better to deliver most mail (even if some are fake or spammy) rather than risk dropping legitimate mail. Thus, neither of these techniques individually or combined provide clear guidance to receivers, and the resulting actions can be inconsistent.

Read the rest of this post »

SPF & DKIM: The State of Domain-based Email Authentication – Part 1

Friday, September 1st, 2017

Recent reports on cyber-security threats in the healthcare sector by Verizon, Symantec and Ponemon consistently make several observations:

  • Email-borne malware is on the rise, with such malware delivered via spam or phishing;
  • Small-to-medium sized businesses (from all sectors) have the highest rate of email-delivered malware;
  • Most breaches are caused by negligent employees or contractors.

These conclusions are hardly surprising as email is now an increasingly common part of communications with protected health information (PHI) frequently exchanged amongst employees and patients within a practice, between medical providers, and medical providers and their business associates. The concern for the healthcare industry is the potential violation of the HIPAA privacy rule caused by email-related (and other) breaches, leading to disruptions from loss of data, compliance audits and possibly hefty fines.

No Phishing

We wrote about obvious measures medical providers can take to avoid HIPAA non-compliance in email exchanges such as opt-out email security. That addresses only one aspect of the threat landscape, though – the protection of PHI in email exchanges. Another aspect is more sinister, as it deals with external, malignant actors. These actors use various spoofing techniques to trick patients or employees of a medical practice to react incautiously, often impulsively, to emails supposedly coming from valid sources. These often lead to identity theft, where the damage is more far reaching as the information given up is more long-lived and more widely used and cannot just be erased like revoking a misused credit card.

Read the rest of this post »

Email Identity Protection and LuxSci Email Hosting

Monday, March 9th, 2015

We have just completed a long series of articles discussing how attackers forge email messages and what technologies and techniques can be used to counter these attacks.  See: Email Identity and Forged Email.

In this post, we will discuss some best practices when using LuxSci to maximize your protection against forged email messages.

Read the rest of this post »

LUXSCI