Oct 19, 2026 · 16:00 UTC SEARCH
UNRATED KNOWN EXPLOITED
Vulnerability intelligence

CVE-2026-42897

VendorMicrosoft
ProductMicrosoft
Known exploitedYes
Added to CISA KEVMay 15, 2026
KEV due dateMay 29, 2026
Known ransomware useNot identified by CISA

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.

Required 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.

CISA KEV status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities Catalog. Known ransomware campaign use: Unknown.

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