One of the big issues with the Internet of Things (IoT) is that not all manufacturers of the devices are being careful about security. Many/most of the devices are connected to the Internet (hence the "I"), and some of them do not use strong passwords and security. Some of the devices still have their well-known default passwords because their installers/users haven't bothered to change them, and some devices can be used to bridge past firewalls if they are not installed thoughtfully.
So the meme is poking fun at such IoT devices, pointing out that "Security" did not make it into the acronym.