CVE intelligence

CVE-2026-87696

Vulnerability intelligence

Published Oct 13, 2026Sources checked Oct 21, 2026

7.5HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-87696 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: Oct 13, 2026

Vendor remediation details

Install KB5128896. Install KB5128895. Install KB5128897. Install KB5128898.

Vendor-listed releases

15.02.1748.055
15.02.2562.056
15.02.1544.050
15.01.2507.077

CISA KEVNot listedBased on the latest collected catalog

EPSS0.4%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-87696?

Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.

Source: NVD