What is CVE-2026-69380?

CVE-2026-69380 is a high-severity vulnerability in Microsoft Exchange Server, classified under Missing Authorization. CVSS score: 8.1/10. Published 2026-09-08.

How severe is CVE-2026-69380?

High severity. CVSS v3 base score is 8.1 out of 10.

Auth bypass in Microsoft Exchange Server

CVE-2026-69380

Missing authorization in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.

Vulnerability class: Broken Access Control

Published 2026-09-08 · last modified 2026-09-29.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.007 (52.2th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 52.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: -0.000

Affected products

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

Microsoft Exchange Server Elevation of Privilege Vulnerability (vendor-advisory, Patch, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-69380?: CVE-2026-69380 is a high-severity vulnerability in Microsoft Exchange Server, classified under Missing Authorization. CVSS score: 8.1/10. Published 2026-09-08.
How severe is CVE-2026-69380?: High severity. CVSS v3 base score is 8.1 out of 10.