Domain-based Message Authentication, Reporting, and Conformance (DMARC) is a critical email authentication protocol standardized by RFC 7489 designed to enhance email security by preventing domain spoofing and email fraud. DMARC builds upon two foundational authentication mechanisms — Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) — by enabling domain owners to publish policies that instruct receiving mail transfer agents (MTAs) on how to handle messages that fail authentication checks.
In today’s cyber threat landscape, robust email security is paramount for organizations leveraging Google Workspace and Gmail as their primary communication tools. Integrating DomainKeys Identified Mail (DKIM) with Sender Policy Framework (SPF) and Domain-based Message Authentication, Reporting, and Conformance (DMARC) offers a comprehensive approach to email authentication and fraud prevention.
DMARC reporting: When to enable it and how to address privacy concerns
by DuoCircle
DMARC reports are an essential aspect of your email authentication setup. Unlike what most organizations think, DMARC is not a one-time stint that you can implement and forget about. To get the most out of the authentication protocol and properly protect your domain, you must stay on top of things and monitor what’s going on in your domain.
We are once again back with fresh news pieces highlighting the important news where major platforms and giant industries have been targeted. To start with, a critical WordPress flaw is being widely exploited to hijack administrator accounts, with over 13,800 attack attempts recorded. SonicWall confirmed that firewall backup files for all cloud backup customers were exposed in a breach, overturning earlier claims of limited impact.
Jaguar Land Rover cyberattack: How a lack of cybersecurity systems led to catastrophe!
by DuoCircle
Jaguar Land Rover, the biggest car manufacturer in the UK, has come to a complete standstill after the recent cyberattack incident. JLR is still struggling with the aftermath of the severe cyberattack. This unfortunate incident is a staggering reminder of how modern-day manufacturers are prone to threat attacks.
Phishing remains one of the most pervasive and damaging cyber threats targeting individuals and organizations worldwide. At its core, phishing involves cybercriminals using deceptive emails, messages, or websites designed to trick users into divulging sensitive information such as login credentials, financial data, or personal identification.
Cold outreach has always been a tightrope walk. On the other hand, businesses and recruiters are seeking to connect with new prospects and initiate conversations. On the other, sending too many emails to the wrong people at the wrong time can harm the sender’s reputation, kill deliverability, and even have a domain blacklisted.
Setting up DomainKeys Identified Mail (DKIM) is an essential step in robust email authentication for any custom domain. By integrating an email DKIM check into your domain environment, you significantly enhance email security, improve email deliverability, and reduce the risk of email spoofing and phishing attacks.
Why SPF, DKIM, and DMARC are becoming mandatory in sectors like aviation and energy
by DuoCircle
Email-based cyberattacks are everywhere. They are more rampant in some industries and have grave consequences in others. For sectors that operate on very high stakes, like aviation and energy, the impact of these attacks is usually very serious and sometimes, at a scale that can disrupt other critical services as well.
In today’s digital landscape, ensuring robust email security is paramount for organizations and domain owners alike. The rise of email phishing attacks, domain spoofing, and other forms of email fraud necessitates advanced solutions that not only detect but also prevent unauthorized email activity.
It was a busy week for cybersecurity threats. Hackers exploited a flaw in VMware software, giving them full control over virtual machines. At the same time, Microsoft flagged a phishing campaign that used AI written code in fake file sharing emails to trick victims. A new Android Trojan, Datzbro, also spread through fake senior community apps, letting criminals take over phones. To top it off, the Confucius group launched fresh phishing attacks, and researchers found a malicious Python package that secretly installed backdoors on Windows systems.
The Simple Mail Transfer Protocol (SMTP) stands as the cornerstone of email delivery across the internet. As an email protocol, SMTP is responsible for the sending and relaying of messages between email servers in the TCP/IP suite. Designed originally in the 1980s, SMTP governs the outgoing mail server infrastructure and serves as the standard method used by mail transfer agents (MTAs) such as Postfix, Sendmail, Exim, and Microsoft Exchange Server to forward email from a mail user agent (MUA) or an email client to the destination email server.
Invoice fraud doesn’t start with a Hollywood-grade hack. It starts with a believable message, a familiar vendor name, and a PDF that looks routine. Attackers know accounts payable runs on documents, so they hide social engineering and malware inside “invoice” attachments to reroute payments or plant a foothold. This guide lays out a practical, technical path to process PDF invoices safely—without turning your finance team into part-time security analysts.
DomainKeys Identified Mail (DKIM) is a critical component of modern email authentication frameworks designed to enhance email security by verifying sender identities and ensuring message integrity. Introduced as an open standard and formalized by RFC 6376, DKIM employs public key cryptography to cryptographically sign email headers and message body, allowing mailbox providers like Google’s Gmail, Microsoft 365, and Yahoo to verify that emails originate from legitimate senders.
Troubleshooting SPF syntax errors: Tips for fixing the most common mistakes
by DuoCircle
When you configure SPF for your domain, there are a lot of things that can go wrong and wreck your entire setup. And if your SPF configuration is not done right, your emails will be at risk, the risk of being rejected, marked as spam, or worse, being impersonated by threat actors.
An online SMTP server functions as a critical component of the email protocol infrastructure, facilitating the transfer of outgoing emails over the internet. SMTP, or Simple Mail Transfer Protocol, is the standardized protocol that governs how email servers, or mail transfer agents (MTAs), communicate to ensure reliable email delivery. Acting as an outgoing mail server, an SMTP server handles the sending process, routing emails through SMTP relay channels to the recipient’s email server.
This week saw a wave of cyber incidents across critical sectors. A stealthy campaign used the BRICKSTORM backdoor to hide inside networks for over a year, while a flaw in Pandoc was exploited in attempts to steal AWS credentials. Libraesva patched a bug in its Email Security Gateway that attackers are already abusing. Airports across Europe faced massive disruptions after a ransomware attack, and researchers flagged ShadowV2, a new Docker-targeting botnet offering DDoS-for-hire services.
Email hosting servers constitute the backbone of modern business communication infrastructure. At their core, these servers manage the sending, receiving, and storage of electronic mail by leveraging robust email server software. Their configuration involves the integration of various email protocols such as SMTP (Simple Mail Transfer Protocol), IMAP (Internet Message Access Protocol), and POP3 (Post Office Protocol 3), ensuring smooth mail routing between mail transfer agents (MTAs) and mail delivery agents (MDAs). Businesses depend on these servers to provide reliable communication channels facilitated through inbound mail servers, outbound mail servers, and mailboxes with efficient mailbox storage management.
When DKIM is not properly aligned for your domain, your outgoing emails may be at risk of tampering. That means anyone can make unauthorized changes to your email while it’s on the way to the receiver’s inbox, and the recipient might never even know it was altered.
Sender Policy Framework (SPF) is a critical email authentication protocol that plays a vital role in bolstering email security. Essentially, SPF allows domain owners to specify which mail servers are authorized to send emails on their behalf by publishing specific rules within DNS TXT records. This configuration helps receiving mail servers verify if incoming messages claiming to be from a particular domain are indeed sent from legitimate sources.
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