pgEdge Postgres MCP Server up to 1.0.x pl-do mcp_custom_tool/mcp_args sql injection

Summaryinfo

A vulnerability, which was classified as critical, has been found in pgEdge Postgres MCP Server up to 1.0.x. This issue affects some unknown processing of the component pl-do. The manipulation of the argument mcp_custom_tool/mcp_args leads to sql injection. This vulnerability is documented as CVE-2026-126197. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in pgEdge Postgres MCP Server up to 1.0.x and classified as critical. This issue affects an unknown functionality of the component pl-do. The manipulation of the argument mcp_custom_tool/mcp_args with an unknown input leads to a sql injection vulnerability. Using CWE to declare the problem leads to CWE-89. The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

pgEdge Postgres MCP Server enables SQL queries against PostgreSQL databases through Model Context Protocol compatible clients. Prior to 1.1.0, custom pl-do tools interpolated JSON arguments into a PostgreSQL DO block delimited by fixed dollar-quote tags. An argument containing $mcp_custom_tool$ could terminate the block and inject arbitrary SQL statements, while $mcp_args$ could inject procedural code into a plpgsql block. Because the statement used the simple query protocol, injected text could include additional statements and transaction control, bypassing read_only and accessing data or modifying resources available to the connecting role. The issue requires at least one pl-do custom tool; sql and pl-func tools pass arguments as bind parameters and are not affected by this injection mechanism. This issue is fixed in 1.1.0.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-126197 since 11/10/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1505 according to MITRE ATT&CK.

Upgrading to version 1.1.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• pgEdge

Name

• Postgres MCP Server

Version

• 1.0

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion