You have a Lenovo computer ? So make verification more: run (through Windows Command + R) certmgr.msc the program. Then go to the "Root Certification Authorities" and see if you have a certificate issued by, and "Superfish, Inc.". If necessary, right click and delete what not.
Windows Defender now detects it for what it is and will remove it. I wonder if other AV vendors will follow suit?