The former Neighbours star, who played Sienna Cammeniti in the Australian soap, accidentally confirmed that her model partner Nathan Joliffe would be appearing in the reality TV show on Twitter.
Weekend Today reporter Airlie Walsh tweeted McNaught yesterday, saying: "I just saw an ad for The Amazing Race with your beautiful boy. Can't wait for the season premiere!"
McNaught then replied: "Hey babe that's so exciting! OMG where? You actually saw Nath on it? Isn't it still supposed to be secret? Arrrgh! So crazy! (sic)"
A spokesperson for the Seven Network refused to confirm any cast members.