7 Practical DKIM Examples for Securing Your Email Domain

7 Practical DKIM Examples for Securing Your Email Domain

 

DomainKeys Identified Mail (DKIM) is one of the most robust email authentication methods, helping organizations defend against email spoofing, phishing, and spam. By using cryptographic digital signatures and distributing public keys through DNS records, DKIM verifies that outgoing emails are authorized and tamper-free, which is critical for brand protection and maintaining user trust. 

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React2Shell RCE Threat, CodeRED Alert Disruption, Coupang Data Breach – Cybersecurity News [December 01, 2025]

React2Shell RCE Threat, CodeRED Alert Disruption, Coupang Data Breach – Cybersecurity News [December 01, 2025]

React2Shell RCE Threat, CodeRED Alert Disruption, Coupang Data Breach – Cybersecurity News [December 01, 2025]

by DuoCircle

 

Cyber incidents this week hit emergency alerting, e-commerce, infrastructure, and app stacks. To start with, ransomware against the CodeRED platform disrupted local emergency notifications and exposed clear-text passwords. In another incident, a five-month breach at a major East Asian retailer affected tens of millions of customer accounts. Attackers exploited a command injection bug in Array Networks gateways, an admin takeover flaw in the King Addons WordPress plugin, and the React2Shell RCE vulnerability in React and Next.js.

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Guide to DMARC setup for Google Workspace

Guide to DMARC setup for Google Workspace

 

Google Workspace helps businesses send emails every day, but keeping those emails safe is just as important as sending them. Gmail now strongly encourages domains to use DMARC, which tells mail servers how to treat suspicious messages. If you set it up correctly, your emails are more likely to reach inboxes and your brand stays protected. 

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The Ultimate Guide to DKIM Google Verification for Email Security

The Ultimate Guide to DKIM Google Verification for Email Security

 

DomainKeys Identified Mail (DKIM) is a sophisticated email authentication protocol used to help combat email spoofing and to ensure message integrity between the email sender and the email recipient. At its core, DKIM works by adding a unique cryptographic digital signature—known as the DKIM signature—to every outgoing email. This DKIM signature is generated using a private DKIM key, which is securely stored by the email server or email sending platform.

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How to Read DMARC Reports and Analyze Email Authentication Results

How to Read DMARC Reports and Analyze Email Authentication Results

 

DMARC (Domain-based Message Authentication, Reporting, and Conformance) is a crucial email security protocol that prevents email spoofing, phishing attacks, and business email compromise by ensuring that only authorized sources can send email on behalf of a domain. By leveraging SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail), DMARC builds on these foundational email authentication methods to provide domain owners with granular control and visibility over their email traffic.

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The Difference Between ~all, -all, and +all in SPF

The Difference Between ~all, -all, and +all in SPF

 

SPF is the foundation of your email authentication, as it tells the receiving servers, “these are the only servers and addresses allowed to send emails on our behalf.” So, when an email goes out from your side to a provider like Gmail or Microsoft Outlook, their servers pull out your SPF record to confirm if the email came from a server you actually approved. If the server matches one of the entries in the list, the email is delivered. 

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ToddyCat APT Evolving, Harvard Breach Reported, SitusAMC Vendor Breach– Cybersecurity News [November 24, 2025]

ToddyCat APT Evolving, Harvard Breach Reported, SitusAMC Vendor Breach– Cybersecurity News [November 24, 2025]

ToddyCat APT Evolving, Harvard Breach Reported, SitusAMC Vendor Breach– Cybersecurity News [November 24, 2025]

by DuoCircle

Cyber incidents this week included ToddyCat deploying new tools to steal email data, Harvard reporting a breach affecting its alumni community, and a vendor compromise at SitusAMC exposing corporate records tied to major banks. Alongside, Asahi confirmed data theft affecting two million individuals, and OpenAI disclosed limited user information exposure linked to a Mixpanel breach. Here are this week’s top headlines.

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How to fix the 550-5.7.26 Gmail error?

How to fix the 550-5.7.26 Gmail error?

 

You might have been sending emails using Gmail for years now, but that’s not a good enough reason for the Email Service Provider (ESP) to let your email in, even if it feels like something’s off. Since email-based attacks are becoming so frequent and rampant, your sender reputation and good faith no longer suffice, given today’s threat landscape. That is why Gmail and other ESPs verify every email they receive before delivering it to the recipient’s inbox

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How cybercriminals use DNS hijacking to bypass DMARC policies

How cybercriminals use DNS hijacking to bypass DMARC policies

 

Email authentication protocols like SPF, DKIM, and DMARC are supposed to stop attackers from pretending to be you and dupe your clients. But what if they target the very system that these protocols depend on?

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