Published Apr 22, 2026Sources checked Oct 28, 2026
6.1MEDIUMCVSS out of 10
What this means
Review the available evidence
CVE-2026-6019 and is rated Medium severity with a CVSS score of 6.1. 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 21, 2026
Release Notes
CISA KEVNot listedBased on the latest collected catalog
EPSS0.2%Estimated 30-day exploitation probability
Ransomware useNot markedCISA KEV ransomware field
Threat actors0Source-linked actor relationships
Overview
What is CVE-2026-6019?
http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element.
Mitigation base64-encodes the cookie value to disallow escaping using cookie value.