CVE-2026-42897—Microsoft Exchange Server Cross-Site Scripting Vulnerability

Vulnerability Name

Microsoft Exchange Server Cross-Site Scripting Vulnerability

Description

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.

Known To Be Used in Ransomware Campaigns?

Ransomware Status:

Unknown

Action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Additional Notes

• https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-42897
• https://learn.microsoft.com/en-us/exchange/plan-and-deploy/post-installation-tasks/security-best-practices/exchange-emergency-mitigation-service
• https://nvd.nist.gov/vuln/detail/CVE-2026-42897

Related News Articles

• Microsoft June 2026 Patch Tuesday fixes 6 zero-days, 200 flawsJune 9, 2026
• Microsoft patches Exchange Server zero-day exploited in attacksJune 10, 2026
• Microsoft Warns of Two Actively Exploited Defender VulnerabilitiesMay 21, 2026

Related Weaknesses

• CWE-79