From inspecting the poster myself, I can say it is no different than an attractive woman wearing a bikini. The actress in the poster is rather skinny, so that are nethers are more prominent, but she is completely covered.

You might be interested to know in New York, it is perfectly legal for a woman to walk around topless, since it would be discrimination to let a man do the same and not a woman. It may be against most people's standards of dress, but in this poster, nothing more is showing than you wouldn't see at the beach (but usually don't since most people are unattractive, including myself).