Even though CBS passed on renewing Supergirl for a second season, leading the show to be picked up by CW, the network says they're not done with superhero programming - they just haven't found the right project yet.
"If we heard the right superhero pitch and we thought it was right for us, we would absolutely buy it," CBS President Greg Geller said at a Television Critics Association event (via Polygon). "We haven't heard anything along those lines as of right now."
CBS passing on Supergirl left them the only major network(including NBC, Fox, and ABC) without a superhero-themed show currently airing or in production.
Although not home to any superhero shows at this time, over the years CBS has had several successful superhero series ranging from Shazam!, Wonder Woman, Amazing Spider-Man, The Incredible Hulk, The Flash, and most recently, Supergirl. The closest thing they have is their partial ownership stake in the CW with Warner Bros.