Type confusion with PostgreSQL internal data type arguments allows any user to execute arbitrary code as the operating system user running the database, via calls to functions with that argument type. Type internal represents a class of mutually-incompatible data structures not intended for access from SQL. The system intended to prevent such function calls, but this prevention had gaps. Versions before PostgreSQL 18.5, 17.11, 16.15, 15.19, and 14.24 are affected.
Weakness
The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.
Extended Description
When the product accesses the resource using an incompatible type, this could trigger logical errors because the resource does not have expected properties. In languages without memory safety, such as C and C++, type confusion can lead to out-of-bounds memory access. While this weakness is frequently associated with unions when parsing data with many different embedded object types in C, it can be present in any application that can interpret the same variable or memory location in multiple ways. This weakness is not unique to C and C++. For example, errors in PHP applications can be triggered by providing array parameters when scalars are expected, or vice versa. Languages such as Perl, which perform automatic conversion of a variable of one type when it is accessed as if it were another type, can also contain these issues.