Security1 hOctober 13, 2026, 02:00

CVE-2026-62911: Exchange auth bypass leads to SYSTEM-level RCE

A flaw in Exchange Server's MRSProxy endpoint, CVE-2026-62911, lets attackers bypass authentication and reach remote code execution as SYSTEM. It affects Exchange 2016, 2019 and SE on the 8.0 and 8.1 lines, with roughly 21,899 internet-facing servers still unpatched in September 2026.

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CVE-2026-62911: Exchange auth bypass leads to SYSTEM-level RCE

CVE-2026-62911 affects Exchange Server 2016, 2019 and SE on 8.0 and 8.1 lines
About 21,899 internet-facing Exchange servers were unpatched in September 2026
Public exploit code and a full Python proof of concept exist
Exchange 2016 is past end of life, with fixes only via extended security updates

#Microsoft#Exchange

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