CVE intelligence

CVE-2026-69378

Vulnerability intelligence

Published Sep 8, 2026Sources checked Oct 28, 2026

7.5HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-69378 and is rated High severity with a CVSS score of 7.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 8, 2026

Vendor remediation details

Install KB5121611. Install KB5121610. Install KB5121608. Install KB5121609.

Vendor-listed releases

15.01.2507.073
15.02.1544.046
15.02.2562.049
15.02.1748.051

CISA KEVNot listedBased on the latest collected catalog

EPSS1.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-69378?

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

Source: NVD