Cursor is a code editor built for programming with AI. Prior to 0.51.0, by default, the setting json.schemaDownload.enable was set to True. This means that by writing a JSON file, an attacker can trigger an arbitrary HTTP GET request that does not require user confirmation. Since the Cursor Agent can edit JSON files, this means a malicious agent, for example, after a prompt injection attack already succeeded, could trigger a GET request to an attacker controlled URL, potentially exfiltrating other data the agent may have access to. This vulnerability is fixed in 0.51.0.