Possible Clues:

• Legitimate object of ridicule
• Aunt Sally? Aunt Sally!
• Aunt Sally, for example, may be legitimate prey
• Open to attack, and based on the starts of the answers to starred clues, what this puzzle is
• Legitimate target in 'Splat the Rat', say
• OK to target
• Aunt Sally?
• A legitimate target, Aunt Sally for example
• Carnival in 24 across is a legitimate target
• Legitimate target for attack or exploitation