Microsoft Exchange Server Cross-Site Scripting Vulnerability
Known exploited
CVE-2026-42897
Summary
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.
Why it matters
CVE-2026-42897 is listed in CISA's Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. CISA remediation deadline: 2026-05-29. Treat remediation as urgent.
Operator check
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Sources
PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.