CVE intelligence

CVE-2026-55008

Vulnerability intelligence

Published Jul 14, 2026Sources checked Nov 12, 2026

9.6CRITICALCVSS out of 10

What this means

Review the available evidence

CVE-2026-55008 and is rated Critical severity with a CVSS score of 9.6. 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: Jul 14, 2026

Vendor remediation details

Install KB5103215. Install KB5103214. Install KB5103213. Install KB5103212.

Vendor-listed releases

15.01.2507.071
15.02.1544.043
15.02.1748.048
15.02.2562.045

CISA KEVNot listedBased on the latest collected catalog

EPSS0.9%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-55008?

Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.

Source: NVD