A critical vulnerability in Microsoft’s open-source UFO automation framework, tracked as CVE-2026-73296 with a CVSS score of 9.4, could allow remote attackers to view and control Android devices without authentication or user interaction.

The flaw, tracked as CVE-2026-73296, has a CVSS severity score of 9.4 out of 10. The issue affects Microsoft UFO versions before 3.0.8 when the Mobile Model Context Protocol (MCP) services are configured for remote access.

Microsoft has released UFO version 3.0.8 to address the problem. UFO includes Mobile MCP servers designed to collect data from and automate Android devices connected via Android Debug Bridge (ADB).

The services can be exposed over HTTP for remote use. The vulnerable data-collection server listens on TCP port 8020, while the action server uses TCP port 8021.

When administrators follow the project’s remote deployment model and bind these services to 0.0.0.0, any system able to reach those ports may be able to use the Android automation functions.

Microsoft UFO Flaw

Researchers found that the servers did not enforce authentication before accepting MCP requests. This meant attackers could initialize a session and execute sensitive actions without supplying a valid credential.

The vulnerability exists in the mobile_mcp_server.py component, specifically in the functions that create the Mobile data-collection and action servers.

According to the GitHub Advisory GHSA-24fq-m9rr-g3mm, the issue is categorized as CWE-306 (Missing Authentication for Critical Function) and CWE-862 (Missing Authorization).

An exposed Mobile MCP data server can provide attackers with screenshots, UI hierarchy information, installed application details, window-control data, and Android device metadata.

This could expose highly sensitive information visible on a phone or emulator screen, including chat messages, email content, one-time passwords, account details, business applications, and authentication prompts.

The action server is more serious because it exposes ADB-backed control features. An unauthenticated attacker may be able to tap arbitrary screen locations, swipe, type text, trigger Android key events, launch applications, and click user interface controls.

In practical terms, an attacker could interact with an unlocked, connected device in the same way as an automation workflow would. The full impact depends on the device state, active applications, and permissions available to the ADB process.

However, the flaw can enable unauthorized changes and disrupt normal device use. The default UFO configuration binds the Mobile MCP services to localhost, which limits network exposure in unchanged installations.

The vulnerability becomes especially dangerous when operators deliberately expose the services through a non-loopback address for remote deployment.

Organizations running UFO with an Android device or emulator connected to the server’s ADB instance should verify that ports 8020 and 8021 are reachable from other systems. Network firewalls can reduce exposure, but they are not a substitute for application-level authentication.

Administrators should upgrade to UFO version 3.0.8 or later immediately. The fixed release adds mandatory bearer token authentication to the Mobile MCP servers.

It uses the UFO_MCP_API_KEY environment variable to handle credentials. The updated implementation is designed to refuse startup when the required API key is missing.

Until all systems are updated, organizations should restrict the Mobile MCP services to localhost, block inbound access to ports 8020 and 8021, and avoid exposing them directly to the internet. Remote deployments should use TLS and an authenticated reverse proxy or a trusted private tunnel.

Security teams should also identify hosts running UFO, review ADB-connected devices and emulators, rotate credentials that may have appeared on exposed screens, and investigate unusual automation activity involving unexpected taps, text entry, app launches, or screenshots.

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