An OS command injection weakness in the read-only enforcement of the SQL validation component in Amazon awslabs postgres-mcp-server before 1.1.7 might allow an unauthenticated actor to execute operating system commands on the host of a self-managed PostgreSQL server by placing a crafted COPY ... TO PROGRAM statement into content that is processed when an authenticated user interacts with the MCP server in its default read-only mode.
To remediate this issue, users should upgrade to version 1.1.7 or later.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 3
https://aws.amazon.com/security/security-bulletins/2026-104-aws/
ff89ba41-3aa1-4d27-914a-91399e9639e5
https://github.com/awslabs/mcp/security/advisories/GHSA-fph8-pg5w-78fv
ff89ba41-3aa1-4d27-914a-91399e9639e5
https://pypi.org/project/awslabs.postgres-mcp-server/1.1.7/
ff89ba41-3aa1-4d27-914a-91399e9639e5