Susceptible
Refers to being likely to be influenced or harmed by a particular thing. It can also mean having a sensitive or responsive nature.
Children with weaker immune systems are more susceptible to seasonal illnesses like the flu.
Precarious
Describes something that is not securely held or in position, likely to fall or collapse, or a situation that is uncertain or risky.
The hikers carefully crossed the precarious bridge, which swayed dangerously with each step.