What is CVE-2025-9866?

CVE-2025-9866 is a security advisory published by Microsoft Security Response Center (MSRC). Chromium: CVE-2025-9866 Inappropriate implementation in Extensions

Which CVE IDs does CVE-2025-9866 cover?

CVE-2025-9866 covers the following CVE IDs: CVE-2025-9866. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

CVE-2025-9866

Chromium: CVE-2025-9866 Inappropriate implementation in Extensions

Vendor

Microsoft Security Response Center (MSRC)

Published

June 3, 2026

Last Modified

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🔗 CVE IDs covered (1)

CVE-2025-9866 →

🔗 CVE IDs covered (1)

📋 Description