Vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23

CVE-2026-69378

Uncontrolled recursion in Microsoft Exchange Server allows an unauthorized attacker to deny service over a network.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-69378?
CVE-2026-69378 is a high-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23, classified under Uncontrolled Recursion. CVSS score: 7.5/10. Published 2026-09-08.
How severe is CVE-2026-69378?
High severity. CVSS v3 base score is 7.5 out of 10.