Microsoft Exchange
Unpatched Microsoft Exchange Server vulnerability exploited (CVE-2026-42897)
A critical cross-site scripting (XSS) vulnerability (CVE-2026-42897) in Microsoft Exchange Server is being exploited by attackers, Microsoft warned on Thursday. A permanent …
The Exchange Online security controls organizations keep getting wrong
In this Help Net Security interview, Scott Schnoll, Microsoft MVP for Exchange, breaks down the Shared Responsibility Model, where Microsoft secures the cloud while …
Microsoft adds high-volume email sending to Exchange Online
Organizations that rely on Exchange Online for internal communications have long needed a way to send large volumes of automated messages, such as payroll notifications, IT …
CISA and partners take action as Microsoft Exchange security risks mount
In partnership with international cybersecurity agencies, the US Cybersecurity and Infrastructure Security Agency (CISA) and the National Security Agency (NSA) outlined …
Microsoft patches three zero-days actively exploited by attackers
On October 2025 Patch Tuesday, Microsoft released fixes for 175+ vulnerabilities, including three zero-days under active attack: CVE-2025-24990, CVE-2025-59230, and …
Microsoft urges admins to plug severe Exchange security hole (CVE-2025-53786)
“In an Exchange hybrid deployment, an attacker who first gains administrative access to an on-premises Exchange server could potentially escalate privileges within the …
Researchers unearth keyloggers on Outlook login pages
Unknown threat actors have compromised internet-accessible Microsoft Exchange Servers of government organizations and companies around the world, and have injected the …
Microsoft enforces defenses preventing NTLM relay attacks
Since making Kerberos the default Windows authentication protocol in 2000, Microsoft has been working on eventually retiring NTLM, its less secure and obsolete counterpart. …
17,000+ Microsoft Exchange servers in Germany are vulnerable to attack, BSI warns
Around 12% of the 45,000 or so Microsoft Exchange servers in Germany that can be accessed from the Internet without restrictions “are so outdated that security updates …
March 2024 Patch Tuesday: Microsoft fixes critical bugs in Windows Hyper-V
On this March 2024 Patch Tuesday, Microsoft has released fixes for 59 CVE-numbered vulnerabilities, but – welcome news! – none of them are currently publicly known …
Microsoft patches two zero-days exploited by attackers (CVE-2024-21412, CVE-2024-21351)
On February 2024 Patch Tuesday, Microsoft has delivered fixes for 72 CVE-numbered vulnerabilities, including two zero-days (CVE-2024-21412, CVE-2024-21351) that are being …
Russian hackers use old Outlook vulnerability to target Polish orgs (CVE-2023-23397)
Russian state-backed hacking group Forest Blizzard (aka Fancy Bear, aka APT28) has been using a known Microsoft Outlook vulnerability (CVE-2023-23397) to target public and …
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