What is CVE-2026-100303?

CVE-2026-100303 is a medium-severity vulnerability in Tduckcloud Tduck-Survey-Form, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-09-25.

How severe is CVE-2026-100303?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Auth bypass in Tduckcloud Tduck-Survey-Form

CVE-2026-100303

TDuck survey form through 6.0 lacks authorization checks on FormThemeController write endpoints for global form themes and categories. Authenticated non-admin users can add, modify, or delete themes and theme categories affecting forms owned by other users.

Vulnerability class: Broken Access Control

Published 2026-09-25 · last modified 2026-09-30.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.003 (20.4th percentile), scored 2026-11-10.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 20.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Tduckcloud Tduck-Survey-Form

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

github.com/LinYuanyi1/cve-request-poc/blob/adffc39b78cad18cd489cbf7454853bf0f74… (exploit)
github.com/TDuckCloud/tduck-survey-form (product)
github.com/TDuckCloud/tduck-survey-form/blob/43ffa9c993e38936fc4de7d8e5aee82bba… (technical-description)
VulnCheck Advisory: TDuck survey form through 6.0 Missing Authorization in Form Theme Management Endpoints (third-party-advisory)

Frequently asked questions

What is CVE-2026-100303?: CVE-2026-100303 is a medium-severity vulnerability in Tduckcloud Tduck-Survey-Form, classified under Missing Authorization. CVSS score: 5.4/10. Published 2026-09-25.
How severe is CVE-2026-100303?: Medium severity. CVSS v3 base score is 5.4 out of 10.