What is CVE-2026-65813?

CVE-2026-65813 is a medium-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.5/10. Published 2026-08-11.

How severe is CVE-2026-65813?

Medium severity. CVSS v3 base score is 6.5 out of 10.

SSRF in Microsoft Exchange Server 2016 Cumulative Update 23

CVE-2026-65813

Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.

Vulnerability class: SSRF (Server-Side Request Forgery)

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Microsoft Exchange Server 2016 Cumulative Update 23 — versions 15.01.0.0
Microsoft Exchange Server 2019 Cumulative Update 14 — versions 15.02.0.0
Microsoft Exchange Server 2019 Cumulative Update 15 — versions 15.02.0.0
Microsoft Exchange Server Subscription Edition Rtm — versions 15.02.0.0

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

secure@microsoft.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-65813?: CVE-2026-65813 is a medium-severity vulnerability in Microsoft Exchange Server 2016 Cumulative Update 23, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.5/10. Published 2026-08-11.
How severe is CVE-2026-65813?: Medium severity. CVSS v3 base score is 6.5 out of 10.