Affected: Go: github.com/jackc/pgx, Go: github.com/jackc/pgx/v4, Go: github.com/jackc/pgx/v5

### Impact

SQL injection can occur if an attacker can cause a single query or bind message to exceed 4 GB in size. An integer overflow in the calculated message size can cause the one large message to be sent as multiple messages under the attacker's control.

### Patches

The problem is resolved in v4.18.2 and v5.5.4.

### Workarounds

Reject user input large enough to cause a single query or bind message to exceed 4 GB in size.