Insubstantial and Open to attack

Insubstantial adjective - Being of a material lacking in sturdiness or substance.

Open to attack and insubstantial are semantically related In some cases you can use "Open to attack" instead an adjective "Insubstantial".

Insubstantial and open to attack are semantically related in dangerous topic. Sometimes you can use "Insubstantial" instead an adjective phrase "Open to attack", if it concerns topics such as insecure.