CVE-2026-58500: Appium Appium-Mcp

High severity, CVSS 8.2. EPSS: 0.4% chance of exploitation in the next 30 days.

MCP Appium is an MCP server that provides AI assistants with tools to automate mobile app testing on Android and iOS. In versions prior to 1.85.10, the createLocatorGeneratorUI function interpolates attacker-controlled element attributes — text, content-desc, resource-id, and locator selector values — directly into an HTML template literal without any HTML or JavaScript context escaping. An attacker who controls the UI of the app under test can inject arbitrary HTML and JavaScript into the MCP UI resource returned by the generate_locators tool. When a victim's MCP client renders this resource, the injected script executes and can invoke arbitrary MCP tools via window.parent.postMessage, leading to unauthorized MCP tool execution such as taking screenshots, reading page source, or any other registered capability. This issue has been fixed in version 1.85.10.

Affected products

• Appium Appium-Mcp: up to and including 1.85.9

Published 2026-07-13. Last modified 2026-08-26.