SQL Injection Vulnerability in pgEdge Postgres MCP Server

CVE-2026-126197

What is CVE-2026-126197?

The pgEdge Postgres MCP Server allows SQL query execution against PostgreSQL databases but has a vulnerability in versions prior to 1.1.0. This flaw can lead to SQL injection attacks via custom pl-do tools. Specifically, arguments containing $mcp_custom_tool$ can terminate the SQL block and enable arbitrary SQL statement injection, while $mcp_args$ can allow the insertion of procedural code within a plpgsql block. Due to the use of the simple query protocol, malicious input can manipulate statements and transaction controls, potentially bypassing read-only restrictions and compromising data integrity or availability. The issue has been resolved in version 1.1.0 to enhance the security posture.

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