--- title: "CVE-2026-96940: Microsoft Exchange Server - Broken Access Control" description: "Microsoft Exchange Server contains a broken access control vulnerability caused by weak authorization, letting authenticated attackers elevate privileges over a network, exploit requires attacker authentication." url: https://panop.io/threat-heartbeat/CVE-2026-96940/ --- # CVE-2026-96940 Microsoft Exchange Server - Broken Access Control Microsoft Exchange Server contains a broken access control vulnerability caused by weak authorization, letting authenticated attackers elevate privileges over a network, exploit requires attacker authentication. CVSS base score 8.8 /10 High CISA KEV Not listed Public exploit Proof of concept available Authentication Required EPSS 0.50% chance of exploitation in 30 days [View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-96940) ## Details Type Broken Access Control Impact Privilege Escalation CVSS vector CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Published 2 October 2026 Updated 15 October 2026 Weakness [CWE-1390](https://cwe.mitre.org/data/definitions/1390.html) ## Vendor fix Update to the latest available version of Microsoft Exchange Server. Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them. ## References - [https://nvd.nist.gov/vuln/detail/CVE-2026-96940](https://nvd.nist.gov/vuln/detail/CVE-2026-96940) - [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96940](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96940) [← All CVEs](https://panop.io/threat-heartbeat/) ## What this record can't tell you - Whether you run the affected software, and where - Whether an attacker can actually reach and exploit it - The misconfigurations that never get a CVE number - What it would cost the business, ranked into what to fix first Panop answers these inside your environment, for this CVE and every other finding. [Book a demo](https://panop.io/demo)