How severe is CVE-2026-48989?

CVE-2026-48989 has a CVSS 4.0 base score of 8.9, rated high severity.

Is CVE-2026-48989 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-48989?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-48989 have an EU (EUVD) identifier?

Yes. CVE-2026-48989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37800.

When was CVE-2026-48989 published?

CVE-2026-48989 was published on 2026-06-17 and last updated on 2026-06-23.

CVE-2026-48989

CVE-2026-48989 is a high-severity vulnerability with a CVSS 4.0 base score of 8.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-306.

Key facts

Severity: High (CVSS 4.0 base score 8.9)
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37800
Weakness: CWE-306
Published: 2026-06-17
Last modified: 2026-06-23

Description

Windows-MCP is an open-source project that integrates AI agents with Windows. In versions prior to 0.7.5, certain HTTP modes exposed the MCP control plane without authentication while enabling wildcard CORS (allow_origins=*, allow_methods=*, allow_headers=*). Because the same server also exposed a PowerShell tool that executes caller-controlled commands as the Windows user running Windows-MCP, attackers could reach the control plane from arbitrary origins or non-browser clients and achieve arbitrary PowerShell execution. This issue was fixed in version 0.7.5.

Frequently asked questions

What is CVE-2026-48989?: Windows-MCP is an open-source project that integrates AI agents with Windows. In versions prior to 0.7.5, certain HTTP modes exposed the MCP control plane without authentication while enabling wildcard CORS (allow_origins=*, allow_methods=*, allow_headers=*). Because the same server also exposed a PowerShell tool that executes caller-controlled commands as the Windows user running Windows-MCP, attackers could reach the control plane from arbitrary origins or non-browser clients and achieve arbitrary PowerShell execution. This issue was fixed in version 0.7.5.
How severe is CVE-2026-48989?: CVE-2026-48989 has a CVSS 4.0 base score of 8.9, rated high severity.
Is CVE-2026-48989 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-48989?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-48989 have an EU (EUVD) identifier?: Yes. CVE-2026-48989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37800.
When was CVE-2026-48989 published?: CVE-2026-48989 was published on 2026-06-17 and last updated on 2026-06-23.

References

Other CWE-306 (Missing Authentication for Critical Function) vulnerabilities

CVE-2026-54309 — Critical (CVSS 10.0): n8n is an open source workflow automation platform. Prior to 2.25.7 and 2.26.2, when @n8n/mcp-browser is run in HTTP…
CVE-2026-50242 — Critical (CVSS 10.0): In JetBrains Hub before 2026.1.13757, 2025.3.148033, 2025.2.148048, 2025.1.148120, 2024.3.148430, 2024.2.148429…
CVE-2026-49257 — Critical (CVSS 10.0): mcp-pinot is a Python-based Model Context Protocol (MCP) server for interacting with Apache Pinot. In versions 3.0.1…
CVE-2026-46846 — Critical (CVSS 10.0): Vulnerability in the Oracle WebCenter Portal product of Oracle Fusion Middleware (component: Security Framework).…
CVE-2026-46803 — Critical (CVSS 10.0): Vulnerability in the Oracle WebCenter Portal product of Oracle Fusion Middleware (component: Security Framework).…
CVE-2026-46800 — Critical (CVSS 10.0): Vulnerability in the Oracle WebCenter Sites product of Oracle Fusion Middleware (component: WebCenter Sites).…

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