Coverage › CVE-2026-42897
CVE-2026-42897 Unmapped
Microsoft Exchange Server Cross-Site Scripting Vulnerability
- Vendor / product
- Microsoft — Microsoft
- Description (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.
- Added to KEV
- 2026-05-15 — after the latest CTID mapping snapshot (2025-07-28)
- Due date
- 2026-05-29
- 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.
- Known ransomware use
- Unknown
- CWE
- CWE-79
- CISA 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 - Elsewhere
- cve.org · NVD · CISA KEV · JSON
ATT&CK techniques
No public source states how this vulnerability is exploited in ATT&CK terms.
The only authoritative CVE → ATT&CK mapping in the open — CTID's Mappings Explorer, pinned to a KEV snapshot of 2025-07-28 and ATT&CK 16.1 — does not include CVE-2026-42897. This entry was added to KEV on 2026-05-15, after that snapshot; of the 283 entries added since, 0 have a mapping. CISA's catalogue carries no technique field. kevmap does not infer techniques from the CWE (CWE-79) — here is why — and does not guess.
This page will change state automatically if a mapping is published. What is shown above is everything CISA publishes about the entry.