---
id: "CVE-2026-126196"
page: "https://infrastack.ai/live/CVE-2026-126196"
kind: "vulnerability"
aliases: ["CVE-2026-126196"]
title: "pgEdge Postgres MCP Server: read-only mode can be bypassed to write data"
severity: "high"
cvss: 8.1
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: [{"name": "pgEdge Postgres MCP Server", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["ai-tooling", "mcp", "pgedge", "postgresql"]
not_affected_if: ["read-only-database-role", "version-1.1.0-or-later"]
published_at: "2026-11-12T18:17:24+00:00"
first_seen_at: "2026-11-12T18:40:38+00:00"
updated_at: "2026-11-12T18:42:45+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126196", "first_seen_at": "2026-11-12T18:40:38+00:00"}]
exploit_sources: []
---

# pgEdge Postgres MCP Server: read-only mode can be bypassed to write data

Link for people: https://infrastack.ai/live/CVE-2026-126196 (this .md is for agents)

The pgEdge Postgres MCP Server lets MCP clients run SQL against PostgreSQL. Before 1.1.0, statements sent to query_database on a read-only connection could chain multiple semicolon-separated statements, letting a caller change data or session state when the database role had write privileges.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:pgEdge Postgres MCP Server affected range not listed fixed no fixed version listed

## How to check

- Check the installed pgEdge Postgres MCP Server version; anything before `1.1.0` is affected.
- Check whether connections rely on `read_only` as the write-protection boundary and whether the connecting database role has write privileges.

## Fix

- pgEdge Postgres MCP Server: upgrade to `1.1.0`.

## Timeline

- 2026-11-12T18:40:38+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126196

## Documents

- [advisory] Vendor advisory: github.com https://github.com/pgEdge/pgedge-postgres-mcp/security/advisories/GHSA-j7mp-839j-jrm7
- [fix] Patch: github.com https://github.com/pgEdge/pgedge-postgres-mcp/commit/b5b929305de7a22cd6ed7de8ae1be2ac90ca0868
- [fix] Release notes: github.com https://github.com/pgEdge/pgedge-postgres-mcp/releases/tag/v1.1.0

## From the sources

pgEdge Postgres MCP Server enables SQL queries against PostgreSQL databases through Model Context Protocol compatible clients. Prior to 1.1.0, query_database on a read_only connection could send unrecognized statements through pgx Exec without bind parameters, selecting PostgreSQL's simple query protocol and allowing multiple semicolon-separated statements in one request. A caller could combine transaction or session state changes with database writes, and pooled session state could leave later calls writable, when the connecting role held write privileges. The flaw affected deployments relying on read_only as a safety boundary, could compromise integrity and availability, and did not add confidentiality impact beyond the reads already permitted by the connection. This issue is fixed in 1.1.0.

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