noun (n)

• the state of being vulnerable or exposed(noun.state)

  Example:
  His vulnerability to litigation.
  

  Synonym:
  exposure
  

  source: wordnet30
• susceptibility to injury or attack(noun.attribute)

  Antonym:
  invulnerability
  

  source: wordnet30
• The quality or state of being vulnerable; vulnerableness.(noun)

  source: webster1913