A runtime inventory is a record of where software components are installed or running, including the versions in use and the people or teams responsible for updating them. It can cover components on servers, in containers, within application stacks, or supplied by a hosting provider.
In cyber security, an accurate inventory helps defenders identify systems that may be affected by a vulnerability and route patches to the right owners. During a security release, teams can use it to locate exposed instances, coordinate updates across different environments, and verify that patched versions are running. Without one, software can be overlooked-especially when it is bundled into images or managed by an external provider.