PoC Released for Microsoft Exchange CVE-2026-62911 Pre

Gbhackers •Divya • September 1, 2026

A public proof-of-concept (PoC) repository has garnered attention for a pre-authentication remote code execution chain targeting Microsoft Exchange Server. This repository highlights CVE-2026-62911, an Exchange authentication-bypass vulnerability disclosed following Pwn2Own Berlin 2026. Defenders should treat the published code as unverified until it is independently validated in an isolated laboratory environment. Both the official advisory and […]

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Critical CVE-2026-62911 Exposes 22,000 Exchange Servers to Remote Code Execution CVE-2026-62911 is a critical authentication bypass vulnerability affecting Microsoft Exchange Server versions 2016, 2019, and Subscription Edition. Disclosed after its demonstration at Pwn2Own Berlin 2026, the flaw allows attackers to exploit NTLM relay attacks via the MRSProxy endpoint, potentially gaining SYSTEM-level control. As of September 1, 2026, nearly 22,000 internet-facing Exchange servers remain vulnerable, with 21,899 unique IP addresses identified by the Shadowserver Foundation. Microsoft released patches on August 2026 Patch Tuesday, but many organizations have yet to apply these updates. The vulnerability has a CVSS score of 8.0 from Microsoft and 8.1 from the Zero Day Initiative, indicating a high severity. The Netherlands National Cyber Security Centre confirmed the availability of exploit code, which is characterized as low-effort and easy to weaponize. Organizations running unpatched versions are urged to apply the updates immediately to mitigate risks. 15 sources 72

Extracted Entities

PoC Released for Microsoft Exchange CVE-2026-62911 Pre

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Extracted Entities

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