CVE-2026-109165
4.3MediumPublished 12 Oct 2026 · NVD status: Deferred · AI triage by gemini-3.8-flash
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Impact
- Limited impact
- Weakness
- CWE-639
Impact
Authenticated attackers can inject arbitrary fields into other users' public survey forms. They only need a valid user account and network access to the API.
Root cause
The batch form creation endpoint only validates ownership on the first element of the array, failing to check authorization on subsequent formKey items.
Affected systems
TDuck survey form through 6.0
CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Fix & remediation
No patched version is specified; block or restrict access to POST /user/form/item/batch/create at your reverse proxy or WAF until a patch is available.
AI-suggested. Run it in staging first and check it against the vendor advisory. Why?
NVD description
TDuck survey form through 6.0 contains a broken access control vulnerability that allows authenticated users to add fields to other users' forms via POST /user/form/item/batch/create. Attackers can submit an array whose first element references their own form and later elements reference a victim's formKey, injecting attacker-chosen fields onto the victim's public fill page.
References
- https://github.com/AnkesKasty/cve-request-poc/blob/a7b6d1423555812d8efa26c91c5d0683164b31e5/tduck/poc_form_item_batch_create_cross_form.py
- https://github.com/TDuckCloud/tduck-survey-form/blob/43ffa9c993e38936fc4de7d8e5aee82bbaa19502/tduck-api/src/main/java/com/tduck/cloud/api/web/controller/UserFormController.java#L327-L336
- https://www.vulncheck.com/advisories/tduck-survey-form-through-6.0-authorization-bypass-via-user-controlled-form-key-in-post-user-form-item-batch-create