fix: the fetch mcp server accepts a user-controlled ... in server.py#4061
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orbisai0security wants to merge 1 commit intomodelcontextprotocol:mainfrom
Open
fix: the fetch mcp server accepts a user-controlled ... in server.py#4061orbisai0security wants to merge 1 commit intomodelcontextprotocol:mainfrom
orbisai0security wants to merge 1 commit intomodelcontextprotocol:mainfrom
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Automated security fix generated by Orbis Security AI
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Summary
Fix critical severity security issue in
src/fetch/src/mcp_server_fetch/server.py.Vulnerability
V-001src/fetch/src/mcp_server_fetch/server.py:99Description: The Fetch MCP server accepts a user-controlled URL parameter and passes it directly to an HTTP client with only a robots.txt check as a security control. Internal services do not serve robots.txt, causing the check to fail open and permit requests to cloud metadata endpoints (e.g., http://169.254.169.254/latest/meta-data/ for AWS IAM credentials), loopback addresses (e.g., http://localhost:6379 for Redis), and RFC-1918 private IP ranges. Any connected MCP client can exploit this without authentication.
Changes
src/fetch/src/mcp_server_fetch/server.pyVerification
Automated security fix by OrbisAI Security