Security Advisory: Anthropic's Slack MCP Server Vulnerable to Data Exfiltration

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<p>This is a security advisory for a data leakage and exfiltration vulnerability in a popular, but now deprecated and unmaintained, Slack MCP Server from Anthropic.</p> <p><img alt="Slack MCP Server" src="https://embracethered.com/blog/images/2025/anthropic-slack-mcp-tn.png" /></p> <p>If you are using this MCP server, or run an &ldquo;MCP Store&rdquo; that hosts it, it is adv