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.
Why should you care about DMARC? What happens if you don’t?
by DuoCircle
Apart from the fact that most major email service providers and organizations have made DMARC mandatory, many teams enable it without fully understanding what it does or why it matters.
Cross tenant mailbox migration is a specialized form of tenant to tenant migration within Microsoft 365 environments, involving the transfer of mailboxes, shared mailboxes, public folders, and associated mailbox data between separate Office 365 tenants. This process is critical in multi-tenant environments where enterprises operate multiple Microsoft Exchange Online tenants, often due to mergers, acquisitions, divestitures, or organizational restructuring.
Cyber incidents this week underline just how disruptive attacks have become. One of the country’s biggest carmakers has kept its production lines shut, losing around 1,000 vehicles a day while work continues to restore systems. Investigators also uncovered a vast ad-fraud scheme that ran across 224 apps with 38 million downloads, generating more than two billion fake ad requests daily. Alongside that, a worm-like breach spread through hundreds of npm packages, while poisoned search results and phishing emails delivered remote-access malware to new victims.
DMARC best practices: Simple steps to protect your domain from email fraud
by DuoCircle
DMARC adoption is on the rise, especially since Google and Yahoo made it mandatory for bulk users. However, it is also true that many domain owners have not figured it out correctly because they don’t follow the best practices associated with it.
An SPF record, or Sender Policy Framework record, is a specific type of DNS TXT record published in the domain name system to improve email authentication and prevent email spoofing. The SPF record syntax defines which IP addresses and email servers are authorized to send emails on behalf of a domain, establishing an email sender policy that email servers can verify during delivery attempts.
Managed services refer to the proactive outsourcing of IT tasks and responsibilities to a third-party provider, enabling businesses to streamline their technology operations while focusing on core competencies. Unlike traditional IT outsourcing, which is often project-based or reactive, managed services emphasize ongoing infrastructure management, performance optimization, and proactive maintenance under a predefined service level agreement (SLA). This approach is designed to maximize system uptime, enhance security posture, and improve operational efficiency.
DomainKeys Identified Mail (DKIM) is a critical component of modern email security standards and plays a vital role in email authentication frameworks alongside Sender Policy Framework (SPF) and Domain-based Message Authentication, Reporting & Conformance (DMARC).
This week’s cyber reports reveal escalating threats on trusted platforms. A significant phishing attack on npm spread malware to millions, while a compromise of Salesloft’s GitHub account impacted the Drift application. Researchers also uncovered a malvertising campaign using fake GitHub commits and detailed the stealthy EggStreme framework, highlighting how attackers are exploiting familiar workflows with increasing sophistication and success.
![JLR Cyber Shutdown, SlopAds App Fraud, Worm Hits npm – Cybersecurity News [September 15, 2025]](https://www.duocircle.com/wp-content/uploads/2025/09/spf-permerror-0009.jpg)
![Malicious npm Packages, Salesloft GitHub Breach, Malvertising Commit Trick – Cybersecurity News [September 08, 2025]](https://www.duocircle.com/wp-content/uploads/2025/09/spf-record-generator-6703.jpg)