All news with #microsoft exchange tag

CISA, NSA and Partners Issue Exchange Server Best Practices

🔐 CISA, the NSA and international partners have published the Microsoft Exchange Server Security Best Practices to help organisations reduce exposure to attacks against hybrid and on‑premises Exchange deployments. The guidance reinforces Emergency Directive 25-02 and prioritises restricting administrative access, enforcing multi‑factor and modern authentication, tightening TLS and transport security, and applying Microsoft's Exchange Emergency Mitigation service. It also urges migration from unsupported or end‑of‑life systems and recommends use of secure baselines such as CISA's SCuBA. Agencies stress ongoing collaboration and a prevention-focused posture despite political and operational challenges.

CISA and NSA Urge Immediate Hardening of Exchange Servers

🔒 CISA, the NSA and international partners have issued urgent guidance to harden on‑premises Microsoft Exchange Server instances by restricting administrative access, enforcing multi‑factor authentication, and applying strict transport security. The agencies recommend migrating or decommissioning end‑of‑life and hybrid Exchange servers, enabling the Exchange Emergency Mitigation Service, and disabling remote PowerShell for users. Organizations are also advised to maintain patch cadence, apply security baselines, and enable antivirus, EDR, ASR, and AppLocker controls.

CISA and NSA Issue Hardening Guidance for Exchange

🔒 CISA and the NSA, joined by the Australian Cyber Security Centre and the Canadian Centre for Cyber Security, released guidance to harden on-premises and hybrid Microsoft Exchange servers against attacks. The advisory emphasizes stronger authentication, minimized application attack surfaces, robust TLS configurations, and decommissioning unsupported servers after migration to Microsoft 365. It also recommends enabling emergency mitigations and built-in anti-spam and anti-malware protections and restricting administrative access to authorized workstations.

Blueprint for Hardening Microsoft Exchange Servers

🔒 CISA, the NSA, and international partners released the Microsoft Exchange Server Security Best Practices blueprint to help administrators of on‑premises and hybrid Exchange environments strengthen defenses against persistent cyber threats. The guidance builds on CISA’s Emergency Directive 25‑02 and emphasizes restricting administrative access, implementing multifactor authentication, enforcing strict transport security, and adopting zero trust principles. It also urges organizations to remediate or replace end‑of‑life Exchange versions, apply recommended mitigations, and consider migrating to cloud-based email to reduce operational complexity and exposure.

Microsoft: Exchange Server 2016 and 2019 End of Support

⚠️ Microsoft notified administrators that Exchange Server 2016 and Exchange Server 2019 reached end of support on October 14, 2025, and will no longer receive security patches or time zone updates after the October 2025 security releases. The company strongly advises migrating to Exchange Online or upgrading to Exchange Server Subscription Edition (SE). In-place upgrades from Exchange 2019 to SE follow the same process as installing a Cumulative Update. Customers still on Exchange 2016 or 2013 should upgrade to SE or first move to Exchange 2019.

Microsoft: Exchange Server 2016/2019 End Support Soon

⚠️ Microsoft has warned that Exchange Server 2016 and Exchange Server 2019 will reach end of extended support on October 14, 2025. After that date Microsoft will stop providing technical support, including bug fixes, time zone updates, and security patches, which could increase exposure to vulnerabilities. Administrators are advised to migrate to Exchange Online or upgrade to Exchange Server Subscription Edition, with documented migration and upgrade paths available.

Microsoft Patch Tuesday: August 2025 Security Fixes

🔒 Microsoft released fixes for more than 100 vulnerabilities in August 2025, including at least 13 rated Critical. Notable flaws include CVE-2025-53786, which lets attackers pivot from compromised on‑premises Exchange Server instances into cloud tenant services, and CVE-2025-53779 (BadSuccessor), a Kerberos dMSA weakness that can yield domain admin rights. Other high‑risk bugs affect GDI+, Word preview and NTLM; several fixes require configuration steps beyond patch installation.

CISA Alerts on Severe Microsoft Exchange Vulnerability

⚠️CISA issued an alert on a high-severity vulnerability affecting on-premise Microsoft Exchange servers disclosed today. The agency is actively monitoring and coordinating mitigation with Microsoft and government and industry partners to assess scope and impact. Organizations are strongly urged to implement Microsoft guidance immediately to reduce risk and protect critical infrastructure.