An editor extension is a plugin that adds features to a code editor or IDE, such as autocomplete, linting, AI assistance, or workflow shortcuts. In modern development tools, extensions can run with meaningful access to files, project settings, clipboard data, and sometimes network connections.
That makes extensions important in cyber security. A malicious or over-permissioned extension can steal source code, read secrets from the workspace, inject unsafe suggestions, or contact external services without clear visibility. Defenders treat extension inventory as part of endpoint security: review trusted sources, restrict installation, monitor permissions and process activity, and remove extensions that are unnecessary or risky. In attacks, the extension is often the delivery point; in defense, it is both an observation point and a control point.