Liam Hemsworth cheating on Miley?

While Miley Cyrus released her risque video “Wrecking Ball,” her purported fiance, Liam Hemsworth, was busy canoodling with another woman at the Toronto Film Festival, spies said.

On Saturday at LDV Hospitality’s pop-up club Bungalow 8 on the Thompson Hotel rooftop, spies saw Hemsworth “locking lips with a random brunette.” Later, “they left together.”

Multiple sources confirmed his smooch with the mystery woman. But Hemsworth’s rep insisted: “There is no truth whatsoever to any of this.”

His rep also shot down a report that Liam was sexting with “Mad Men” star January Jones as “tabloid fiction” and “entirely fabricated.”

Amy Sacco’s Bungalow hosted some of the festival’s hottest parties, including an all-night bash for New York film financier Worldview Entertainment. On Sunday, however, Liam was on his best behavior at a Thompson premiere party for his brother Chris’ film “Rush.”

“Liam raised a glass to toast his big brother,” said a spy at the Grey Goose reception for 500, which included Olivia Wilde and director Ron Howard.