Connected devices have become an integral part of modern homes and household devices, such as vac-uum cleaners and refrigerators, are now often connected to networks. This connectivity introduces an entry point for cyber attackers. The plethora of successful cyber attacks against household IoT indicates that the security of these devices, or the security of applications related to these devices, is often lacking. Existing penetration testing studies usually focus on individual devices, and recent studies often men-tion the need for more extensive vulnerability assessments. Therefore, this study investigates the cyber security of devices commonly located in connected homes. Systematic penetration tests were conducted on 22 devices in five categories related to connected homes: smart door locks, smart cameras, smart car adapters/garages, smart appliances, and miscellaneous smart home devices. In total, 17 vulnerabilities were discovered and published as new CVEs. Some CVEs received critical severity rankings from the National Vulnerability Database (NVD), reaching 9.8/10. The devices are already being sold and used worldwide, and the discovered vulnerabilities could lead to severe consequences for residents, such as an attacker gaining physical access to the house. In addition to the published CVEs, 52 weaknesses were discovered that could potentially lead to new CVEs in the future. To our knowledge, this is the most comprehensive study on penetration testing of connected household products. (c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )