CVE-2026-87911
Deferred Deferred - Pending Action

OS Command Injection in Amazon awslabs postgres-mcp-server

Vulnerability report for CVE-2026-87911, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-09-09

Last updated on: 2026-09-10

Assigner: AMZN

Description

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.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-09-09
Last Modified
2026-09-10
Generated
2026-09-30
AI Q&A
2026-09-10
EPSS Evaluated
2026-09-27
NVD
EUVD

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
amazon awslabs_postgres-mcp-server From 1.1.7 (exc)
amazon postgres-mcp-server 1.1.7

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-78 The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
CWE-184 The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

CVE-2026-87911 is an OS command injection vulnerability in Amazon's awslabs.postgres-mcp-server before version 1.1.7. It allows unauthenticated attackers to execute arbitrary system commands on a self-managed PostgreSQL server by bypassing read-only enforcement and injecting a crafted COPY ... TO PROGRAM statement when an authenticated user interacts with the MCP server.

Detection Guidance

To detect this vulnerability, check the version of awslabs.postgres-mcp-server installed on your system. If it is below 1.1.7, the system is vulnerable. Run: pip show awslabs.postgres-mcp-server or check the package version in your environment. Additionally, review PostgreSQL server logs for suspicious COPY ... TO PROGRAM statements or unexpected command executions.

Impact Analysis

This vulnerability could allow attackers to execute arbitrary operating system commands on the host of a self-managed PostgreSQL server. This may lead to full system compromise, data theft, unauthorized modifications, or service disruption. The impact depends on the server's configuration and privileges.

Compliance Impact

This vulnerability could lead to unauthorized access, data breaches, or data manipulation, which may violate compliance requirements under GDPR, HIPAA, or other regulations. Organizations must address this flaw to maintain data integrity and confidentiality standards.

Mitigation Strategies

Immediately upgrade awslabs.postgres-mcp-server to version 1.1.7 or later. As a temporary workaround, avoid using superuser roles and use a dedicated Postgres role with minimal privileges. Enforce read-only transactions at the role level and ensure the MCP server connects using a low-privilege database role.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-87911. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart