Microsoft has officially announced the end of support for Office Online Server, effective December 31, 2026. This decision affects organizations that rely on on-premises browser-based document editing and viewing capabilities, pushing them toward Microsoft 365 or alternative solutions as they plan their migration strategies.​ What is Office Online Server Office Online Server was designed to provide [...]

Cybersecurity researchers have uncovered a widespread attack campaign exploiting Microsoft 365 Exchange Online's Direct Send feature, allowing threat actors to spoof internal users and deliver phishing emails without compromising a single account. Cisco Talos, Varonis Threat Labs, and multiple email security vendors report that over 70 organizations across various industries have been targeted since May [...]

Microsoft has released critical security updates for Exchange Server, marking a significant milestone as these represent the final publicly available updates for Exchange Server 2016 and 2019. The October 2025 Security Updates (SUs) address multiple vulnerabilities across Exchange Server Subscription Edition (SE), Exchange Server 2019, and Exchange Server 2016.​ Affected Versions and Availability The October [...]

Suspected Chinese hackers have infiltrated the Microsoft Exchange email servers of foreign ministries across Africa, the Middle East, and Asia in a sophisticated, multi-year espionage operation. Researchers at Palo Alto Networks' Unit 42 threat intelligence division revealed the discovery of Phantom Taurus, a previously undocumented nation-state actor conducting intelligence collection operations aligned with People's Republic [...]

With Microsoft retiring support for Exchange Server 2016 and 2019 this month, Exchange Server Subscription Edition (SE) will become the only supported on-premises version. Microsoft has announced a 6-month Extended Security Update (ESU) program to give customers time to complete migrations. Messageware, a leading provider of security solutions for Microsoft Exchange, is pleased to confirm [...]

Microsoft has issued a critical reminder that Exchange Server 2016 and Exchange Server 2019 will reach end of support on October 14, 2025, with less than one month remaining to prepare and act. Organizations must plan an immediate migration path to remain secure and compliant, either to Exchange Online or to the new Exchange Server Subscription Edition [...]

Microsoft has released the September 2025 Hotfix Updates (HUs) for Exchange Server 2016, Exchange Server 2019, and Exchange Server Subscription Edition (SE). These non-security updates address specific issues in earlier releases and include continued support for the dedicated Exchange hybrid app functionality. HUs are available for the following specific versions of Exchange Server: Exchange Server [...]

Messageware is pleased to announce that Messageware AttachView is now fully compatible with Exchange Server SE, delivering complete Outlook Web attachment protection for organizations migrating to or running SE environments. As the only third-party solution purpose-built for Exchange Server SE, AttachView provides unmatched security for Outlook Web attachments. By instantly converting files into secure, browser-based [...]

Microsoft has released the August 2025 Security Updates (SUs) for Exchange Server 2016, Exchange Server 2019, and Exchange Server Subscription Edition (SE). These cumulative updates address multiple vulnerabilities and introduce default security hardening, and they explicitly include the capability required for on‑premises Exchange to support and use the dedicated Exchange hybrid app needed to mitigate [...]

Microsoft has disclosed a high-severity vulnerability in Exchange Server hybrid deployments that poses significant risks to organizations worldwide. CVE-2025-53786, with a CVSS score of 8.0, enables attackers to escalate privileges from on-premises Exchange servers to connected cloud environments without leaving detectable audit trails. The Core Security Flaw The vulnerability exploits a fundamental design weakness in Exchange [...]

A sophisticated new threat has emerged targeting Microsoft Exchange infrastructure worldwide. Kaspersky's Global Research and Analysis Team recently uncovered GhostContainer, a highly advanced backdoor malware that leverages open-source tools to establish persistent access to Exchange servers. This analysis examines the technical mechanisms, attack vectors, and implications of this threat for enterprise security teams managing Exchange deployments. GhostContainer [...]

A critical zero-day vulnerability in Microsoft SharePoint has triggered widespread cyberattacks across the globe, affecting businesses, government agencies, and educational institutions. The attack exploits a previously unknown security flaw that allows hackers to gain complete control over on-premises SharePoint servers without authentication. Microsoft has now directly attributed these attacks to Chinese state-sponsored hacking groups. Scale [...]

Microsoft has announced an optional 6-month Extended Security Update (ESU) program for Exchange Server 2016 and 2019, providing a temporary bridge for organizations struggling to complete their migrations before the upcoming end-of-support deadline. This program represents Microsoft's response to customer feedback indicating that some organizations need additional time to finalize their transitions to Exchange Subscription [...]

The second week of July 2025 marked a significant disruption in Microsoft's cloud ecosystem, with a cascading series of outages that affected millions of users worldwide. What began as isolated reports of service issues on July 9th quickly escalated into one of the most prolonged and impactful outages in Microsoft 365's history, lasting over 19 [...]

Microsoft Exchange Server Subscription Edition (SE) is now available for general release as of July 1, 2025. This marks a significant shift in how Microsoft delivers and supports its on-premises email server solution. What Exchange Server SE Brings to Organizations Exchange Server SE represents the future of Microsoft's on-premises email platform. The product operates under [...]

Active Directory (AD) is a primary target for attackers due to its central role in enterprise authentication and authorization. Password attacks against AD often represent an initial access vector, potentially leading to more severe compromises. A layered defense approach is necessary for robust protection. This document outlines strategies to defend AD against such attacks. Understanding [...]

Hotfix update for Microsoft Exchange Server 2019 CU15 HU2 was released on May 29, 2025. It includes fixes for nonsecurity issues and introduces new features. These fixes and features will also be included in later cumulative updates for Exchange Server 2019.  Microsoft Exchange Server Build Numbers, Cumulative Updates (CU), Security Updates (SU) and Release Dates Microsoft [...]

Introduction to Exchange Server Subscription Edition Microsoft Exchange Server has been a cornerstone of business communication since its initial release in 1993. As we approach the release of Exchange Server Subscription Edition (SE) in the third quarter of 2025, we're seeing a significant shift in Microsoft's approach to on-premises email and collaboration services. This new [...]

Russia's elite cyber espionage unit, Fancy Bear (APT28), has intensified its sophisticated attacks on Microsoft Exchange servers as part of a broader campaign targeting Western organizations supporting Ukraine. The joint cybersecurity advisory released on May 21, 2025, by 21 international intelligence agencies reveals how the Russian General Staff Main Intelligence Directorate (GRU) military unit 26165 [...]