Microsoft Playwright MCP Server < 0.0.40 DNS Rebinding via Missing Origin Header Validation
Priority HIGH 65CWE-749Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.
Summary
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.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01222 68th percentileScored 2026-11-07
Fix Fixed Playwright (Microsoft): 0.0.40@playwright/mcp (npm): 0.0.40
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Playwright | before 0.0.40 | 0.0.40 | Patch available | CNA |
| — | @playwright/mcp (npm) | before 0.0.40 | 0.0.40 | Patch available | GHSA-6fg3-hvw7-2fwq |
- Playwright VendorMicrosoft Affected before 0.0.40 Fixed in 0.0.40 Patch available CNA
- @playwright/mcp (npm) Vendor— Affected before 0.0.40 Fixed in 0.0.40 Patch available GHSA-6fg3-hvw7-2fwq
Remediation
- Fix · CNA Playwright (Microsoft) Fixed in 0.0.40
- Fix · GHSA-6fg3-hvw7-2fwq @playwright/mcp (npm) Fixed in 0.0.40 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-9611
- 2026-10-03 Alias added: GHSA-6fg3-hvw7-2fwq
References
Advisory 2
More Microsoft vulnerabilities
- TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2025-9611 · CVE Program
- CVE-2025-9611 · NVD
- FIRST EPSS
- GHSA-6fg3-hvw7-2fwq · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences