How severe is CVE-2025-9611?

No CVSS score has been assigned to CVE-2025-9611 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-9611?

CVE-2025-9611 affects the following packages: @playwright/mcp (npm). Ecosystems affected: npm.

How do I fix CVE-2025-9611?

Update @playwright/mcp to 0.0.40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-9611 is resolved across your whole dependency graph.

How do I detect CVE-2025-9611 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @playwright/mcp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-9611 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2025-9611?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-9611 can be triaged on real exposure rather than presence alone.

Is CVE-2025-9611 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-9611 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-9611?

CVE-2025-9611 has an EPSS (Exploit Prediction Scoring System) score of 1.2%, placing it in the 67th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-9611?

CVE-2025-9611 is classified as CWE-749 (CWE-749). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-9611 published, and has it been updated?

CVE-2025-9611 was published on January 7, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2025-9611 — @playwright/mcp

Fix: microsoft/playwright@1313fbd

CVE-2025-9611 is a CWE-749 vulnerability in @playwright/mcp. A fix is available for @playwright/mcp — see the affected versions and patch details below.

Microsoft Playwright MCP Server < 0.0.40 DNS Rebinding via Missing Origin Header Validation

Also known asGHSA-6fg3-hvw7-2fwq GHSA-8rgw-6xp9-2fg3

Published

Jan 7, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 21, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-9611.

EPSS Exploitation Probability

via FIRST.org ↗

1.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs67th percentile — riskier than 67% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

115other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

@playwright/mcpnpm

5.2Mdownloads / week

Description

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 Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@playwright/mcp`	all versions	0.0.40`npm install @playwright/mcp@0.0.40`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @playwright/mcp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @playwright/mcp to 0.0.40 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-9611 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-9611 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2025-9611. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2025-9611 in your dependencies?

O3 Security finds CVE-2025-9611 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works