tl;dr There is an adware called Privdog that gets shipped with software from Comodo. It totally breaks HTTPS security.
From Naked Capitalism's summary:
So here we have the CEO of a Certificate Authority (CA), Comodo, who is also the CEO of Privdog, whose product subverts the certificate authority system. Oh, and Comodo ships that very product with its software. These bottom feeders make Bill Gates look like St. Francis of Assisi. How deep does the rot in the software industry go, anyhow?
I am beginning to believe that Richard Stallman is right, living in freedom means using free and open software."