CVE-2025-9611
Microsoft Playwright MCP Server < 0.0.40 DNS Rebinding via Missing Origin Header Validation
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.
Fixes and workarounds
Fix
The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.
Source: CNA: VulnCheckAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Playwright Microsoft %40playwright/mcp
npm |
≥ 0; < 0.0.40 (affected, semver)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 7.2 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:L/SI:L/SA:L | CNA: VulnCheck |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/JLLeitschuh/security-research/security/advisories/GHSA-8rgw-6xp9-2fg3CNA: VulnCheck · vendor-advisory
- https://github.com/microsoft/playwright/commit/1313fbdCNA: VulnCheck · patch
- https://www.vulncheck.com/advisories/microsoft-playwright-mcp-server-dns-rebinding-via-missing-origin-header-validationCNA: VulnCheck · third-party-advisory
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
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Endpoints and access details
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A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.