Underwood started the online buzz about their co-hosting return with a Tweet Wednesday.
"Hanging out with @bradpaisley today. Just caught him in my make up chair. #suchadiva," Underwood said on her Twitter page.
CMA later confirmed the news on Twitter and Facebook with a picture of the two stars during a photo shoot.
The 46th Annual CMA Awards will air live from Nashville on Thursday, Nov. 1, on ABC7.