NEW YORK -- Walt Disney is not going to like this.

A spokesman for Vanessa Hudgens has confirmed that a nude photo circulating on the Internet is indeed that of the 18-year-old star of the Disney Channel's wildly popular "High School Musical."

In the photo, Hudgens is standing naked in what appears to be a bathroom.

MSNBC.com reported a statement from her spokesman said the photo "was taken privately." It adds this is "a personal matter and it is unfortunate that this has become public."

Hudgens is said to be dating her "High School Musical" co-star Zac Efron.

The Disney Channel said that more than 17 million people watched the premiere of "High School Musical 2," which made it most-watched basic cable telecast of all-time.

In addition, the numbers make "High School Musical 2" the No. 1 original movie on basic cable of all time, ousting Tom Selleck's "Crossfire Trail," which aired six years ago on TNT.

"High School Musical 2" is not only a hit with cable viewers -- it's tops with music buyers, too.

According to Walt Disney Records, the soundtrack sold 615,000 copies its first week out to debut at No. 1 on Billboard's Top 200 album chart.

Only Linkin Park's "Minutes to Midnight" sold more copies its first week out this year, with 623,000 copies in June.

The first "High School Musical" movie premiered a year ago, and spawned huge DVD and soundtrack sales, hit singles and a concert tour.