The problem for the Walt Disney Co. is that Hudgens plays Gabriella.
Hudgens' publicist confirmed Friday that the photograph is indeed the 18-year-old star of Disney Channel's wildly successful "High School Musical" franchise. It shows a coquettishly smiling Hudgens posing naked in a bedroom with a red curtain behind her.
"This was a photo which was taken privately," said Jill Fritzo, Hudgens' publicist. "It is a personal matter and it is unfortunate that this has become public."
She wouldn't say anything about who took the picture and how it slipped out onto the Internet.
The Disney Channel (part of the Walt Disney Co.) denied a published report that Hudgens will be dropped from the upcoming feature film "High School Musical 3." That movie is in development and negotiations with the stars are incomplete.
Disney had no further comment about the pictures.
Hudgens portrayed the bookworm love interest of Troy, the basketball star played by pinup king Zac Efron in the first two made-for-cable "High School Musical" movies. The sequel's premiere on Disney Channel last month attracted more than 17 million viewers, making it the summer's most-watched TV program.
She's a superstar among the pre-teen set, and Disney has spun a wide merchandising net around the series with albums and concert tours. She and Efron reportedly date in real life.
The films' wholesome nature - for a company that has made its name on family-friendly fare for generations - is a big part of its success. Parents of the largely pre-teen fan base can relax knowing their children are watching, knowing it won't make for any uncomfortable questions.
Gabriella and Troy coo, they make googly eyes, they barely kiss. They certainly don't show off nude pictures.
If Disney were to dump Hudgens for another actress, not wanting its name associated with anything not G-rated, it runs the risk of upsetting a formula that has made it millions.
How would parents explain to the show's young fans that the old Gabriella had to go?
"That's her private life, not her public life. That picture got leaked by somebody who broke a trust with her," said Michele Smith of Westborough, Mass., whose eight-year-old daughter Kathryn is a devoted "High School Musical" fan.
Hudgens shouldn't have to pay a price for the incident, Smith said, adding she was concerned that Disney's image might prompt the company to take action against the actress.
Dropping her from future movies or other "High School Musical" projects would not only be unfair to Hudgens but to fans such as Kathryn, Smith said.
"If Vanessa is not in the movie, my daughter would not be so excited to see it," she said.
Smith said she hopes that Kathryn doesn't hear about the photo but, if she does, she's prepared to talk about it. She'll say that it's something private for Vanessa that shouldn't have been shared.
The best thing for Disney to do is nothing, said Michael Levine, a Hollywood image consultant and author of 18 books.
"What they shouldn't do is make a bigger deal out of it than is necessary," he said. "The picture is not salacious."
Michael Sands, a publicist whose clients have included Britney Spears' ex-husband Kevin Federline, said Hudgens should be commended for coming forward quickly and saying it was her picture.
He also advised Disney to stand by her.
"This is a big cash cow for Disney," Sands said.
Things like this always happens to celebrities. No wonder I put in my essay that we worship drunk celebs in rehab.