Submission disclosure and overwrite via predictable identifiers

Authorization bypass in editable submissions in OpnForm before 2.0.2 allows remote attackers to read or overwrite submissions via predictable identifiers. SubmissionUrlService and the submission fetch and answer flows treated Hashids-encoded sequential row IDs as bearer secrets, and legacy rows without public_id still accepted identifiers that anyone could derive because the salt was empty. Exploitation requires only a public form slug and affected pre-migration editable submissions; attackers can retrieve another respondent's data or replace it, but the issue does not provide code execution or service interruption.