Chen, 49, who has hosted every season of the competition series, posted a photo on Instagram featuring Big Brother's backdrop and logo, as well as an empty brown set chair in the "diary room."
The October 25 caption was only a winking face emoji and the eyes emoji -- and Chen didn’t elaborate.
Followers speculated that Big Brother will come back for a new season before it typical summer premiere—or that one of its spinoffs could be hitting soon.
The 21st season of the show just ended a month ago.
Fans believe the most plausible explanation behind Chen’s social media post is that it's a sign that Celebrity Big Brother, which ran for two seasons in 2018 and 2019 as the first spinoff, is about to kick off.
Or perhaps the Big Brother streaming spinoff, Big Brother: Over The Top, could come back after that series aired for just one season in 2016 on CBS All Access.
An "All-Stars" season is another possibility.
"There was a rumor out there that we were possibly getting a condensed all-star season, possibly with just winners. I wouldn’t mind some form of All-stars or BBott2. Although, I don’t know if Twitter could handle another season of OTT. We were ridiculous," tweeted user @CynCyn198.
Big Brother 20 alum Haleigh Broucher weighed in online: "Tell me something good, Julie."
Moonves, 69, left as chairman of the eye network on September 9, 2018 after multiple accusations of sexual harassment.
Both Chen and Moonves, 69, staunchly denied the sexual misconduct allegations against him.
She said in a statement at the time, "Leslie is a good man and a loving father, devoted husband and inspiring corporate leader. He has always been a kind, decent and moral human being. I fully support my husband and stand behind him…."
In an emotional announcement in September 2018, Chen told viewers, “I have been at The Talk since the day it began. Right now, I need to spend more time at home with my husband and young son. So I have decided to leave The Talk."
Since then, Chen has been spotted with her husband on ritzy restaurant date nights.
The longtime TV host was devastated when original Big Brother star Cassandra Waldon, 56, reportedly passed away in a car wreck overseas earlier this month.
On October 4, Chen posted Waldon photos on her Instagram account that appeared to show a funeral announcement, and also wrote, "Rest in Peace Cassandra. Your light will continue to shine in this world because of the way you lived your life: with class and grace. May your family and loved ones find solace and peace. Thank you for bringing your intelligence, warmth and wisdom to the Big Brother house Season 1. You are in my thoughts and in my prayers. May God Bless your soul."