CVE-2026-109165 TDuck survey form through 6.0 Authorization Bypass via User-Controlled Form Key in POST /user/form/item/batch/create
Authenticated attackers can inject fields into other users' survey forms by manipulating form keys in batch creation requests.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-109165?
CVE-2026-109165 is a medium-severity missing authorization vulnerability in TDuckCloud tduck-survey-form, published on 12 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-639
Which versions are affected by CVE-2026-109165?
How do I fix CVE-2026-109165?
No fix has been published for CVE-2026-109165 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-109165 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109165 exists.
Sources
Also known as GHSA-xjj9-v7hq-9hc8.