Microsoft Exchange Server contains a cross-site scripting vulnerability during web page generation in Outlook Web Access and when certain interaction conditions are met, arbitrary JavaScript can be executed in the browser context.
Product
Microsoft
Added to KEV
15 May 2026
Federal remediation due
29 May 2026
Known ransomware use
Not reported
Page history
Changes are dated when recorded; day views use the last saved version from that UTC day, and citations stay fixed.
More advisories, affected versions and source history
Related advisories and sources
Publishers link these advisories through the identifiers shown below. A shared identifier or date alone does not tell you whether your software is affected or whether the advisories describe the same cause.