CVE-2026-61529CVE-2026-61529

Endatix is a self-hosted form and survey management platform with a headless API. Prior to 0.7.0, the anonymous `POST /forms/{formId}/submissions` endpoint stores attacker-controlled `JsonData` after checking only that the JSON is well formed. A file object with `name`, `type` and `content` fields can contain an HTTP or HTTPS URL. When a staff member with `submissions.view` permission invokes `POST /forms/{formId}/submissions/{submissionId}/files`, `GetFilesHandler` passes the stored data to `SubmissionFileExtractor` in `src/Endatix.Infrastructure/Features/Submissions/SubmissionFileExtractor.cs`, which calls `HttpClient.GetAsync` without validating the destination URL, host or resolved IP addresses against internal address ranges. This permits stored, second-order server-side GET requests to internal services, cloud metadata, loopback and link-local addresses from the server's network position. The form must have `IsPublic` and `IsEnabled` set, and an anonymous submission must pass reC