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CISA and NSA Microsoft Exchange hardening guidance

Advisory/Mitigation
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Last updated
Happening score
H score 10
2 unique sources, 2 articles

Summary

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CISA and NSA released Microsoft Exchange hardening guidance that pushes administrators to reduce attack surface, strengthen authentication, and retire unsupported servers before they become a breach path. The guidance targets on-premises and hybrid Exchange environments and emphasizes concrete mitigations rather than broad advice. It also reinforces protections for organizations still running end-of-life Exchange deployments after moving to Microsoft 365.

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Microsoft Exchange CVE-2026-42897 mitigation advisory

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First: 15.05.2026 12:40 Last: 15.05.2026 12:40 Sources 1

About this happening: **Microsoft** issued immediate mitigation guidance for **CVE-2026-42897**, reducing risk for **Exchange Server 2016, 2019, and Subscription Edition (SE)** on-premises servers that...

Latest development: 15.05.2026 15:35

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Open Happening

Timeline

  1. 30.10.2025 18:11 2 articles · 6mo ago

    CISA and NSA release Microsoft Exchange hardening guidance

    Initial Disclosure

    CISA and the NSA, joined by the Australian Cyber Security Centre and the Canadian Centre for Cyber Security, released guidance for IT administrators to harden Microsoft Exchange servers against attacks. The guidance recommends stronger user authentication and access controls, reduced application attack surface, stronger network encryption, keeping servers up to date, enabling emergency mitigation services, and retiring end-of-life on-premises or hybrid Exchange servers after moving to Microsoft 365.

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