# CVE-2026-100304: TDuck survey form 6.0 Information Disclosure via Fail-Open Form Ownership Check

> Authenticated users can read deleted form submissions containing personal information due to a fail-open permission check.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Sep 2026
- **Updated:** 29 Sep 2026
- **Also known as:** GHSA-3hhg-8chj-hh93

## What is CVE-2026-100304?

CVE-2026-100304 is a medium-severity vulnerability in TDuckCloud tduck-survey-form, published on 25 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

TDuck survey form 6.0 contains an information disclosure vulnerability in FormAuthUtils.hasPermission that fails open when a form does not exist, allowing authenticated users to access deleted form submissions. Attackers can read orphaned submission data including personal information by providing a known dataId to the GET /user/form/data/details endpoint after the form has been permanently deleted.

Weakness: CWE-636 (Not Failing Securely)

## Which versions are affected by CVE-2026-100304?


## How do I fix CVE-2026-100304?

No fix has been published for CVE-2026-100304 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-100304 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100304 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-100304 and fix it if it is affected.

What it is: CVE-2026-100304 is a medium-severity vulnerability in TDuckCloud tduck-survey-form, published on 25 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-100304 exists.

Affected product: TDuckCloud tduck-survey-form. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-100304/ (Markdown: https://insights.sbomify.com/CVE-2026-100304/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-100304
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-100304
- OSV: https://osv.dev/vulnerability/CVE-2026-100304

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-100304/
Summaries are generated and may contain mistakes; the official description above is the record.