CVE-2025-9611: Microsoft Playwright

High severity, CVSS 7.2. EPSS: 1.2% chance of exploitation in the next 30 days.

Microsoft Playwright MCP Server versions prior to 0.0.40 fails to validate the Origin header on incoming connections. This allows an attacker to perform a DNS rebinding attack via a victim’s web browser and send unauthorized requests to a locally running MCP server, resulting in unintended invocation of MCP tool endpoints.

Affected products

• Microsoft Playwright: before 0.0.40 (fixed in 0.0.40)

Published 2026-01-07. Last modified 2026-10-08.