CVE-2026-126197 pgEdge Postgres MCP Server SQL injection through custom pl-do tool parameters
Attackers can inject SQL through custom pl-do tool arguments in pgEdge Postgres MCP Server, bypassing read-only mode.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Harmful if only installed
- No
- Needs a specific call
- No
- Fix
- None listed
What is CVE-2026-126197?
CVE-2026-126197 is a high-severity SQL injection vulnerability in pgedge-postgres-mcp, published on 12 Nov 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-89
Which versions are affected by CVE-2026-126197?
Only installations with a non-default setting turned on are exposed.
How do I fix CVE-2026-126197?
No fix has been published for CVE-2026-126197 yet. Limit exposure of the affected software until one is available.
Use parameterised queries everywhere and never build SQL by joining strings. Upgrade affected software first; a web application firewall only buys time. More about SQL injection.
Is CVE-2026-126197 being exploited?
There is no known exploitation of CVE-2026-126197 in the wild and no public exploit code.
Sources
Also known as GHSA-r5pp-jx86-r6r9.