CVE-2026-105090
What it is
Formbricks before 5.4.4 and 6 before 6.0.1 allows stored XSS. The survey-level Custom Head Scripts feature did not enforce the documented Manage permission boundary. A workspace member holding only readWrite permission could configure Custom Head Scripts on a survey, an operation the documentation restricts to the Manage role. Because the configured scripts execute in the authenticated browser session of any user who opens the affected survey, a lower-privileged member can run arbitrary JavaScript (stored cross-site scripting) in the session of higher-privileged users. Fixed versions require Manage access to modify survey Custom Head Scripts.
At a glance
- Exploitability
- Can be exploited over the network with a low-privilege account, but needs a user to act. Limited direct impact.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 5.1 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-863 · Incorrect authorization
- Record status
- Awaiting Analysis
Attack profile CVSS 4.0 · 5.1
- Attack vector
- Network
- Complexity
- Low
- Attack requirements
- None
- Privileges needed
- Low
- User interaction
- Passive
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-105090.md and follow it. Check whether this project is affected by CVE-2026-105090. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/formbricks/formbricks/pull/9432
- https://github.com/formbricks/formbricks/releases/tag/5.4.4
- https://github.com/formbricks/formbricks/releases/tag/6.0.1
References
- https://github.com/formbricks/formbricks/pull/9432
- https://github.com/formbricks/formbricks/releases/tag/5.4.4
- https://github.com/formbricks/formbricks/releases/tag/6.0.1
- https://www.sec4check.pl/blog/posts/cve-formbricks-broken-access-control-stored-xss-custom-head-scripts.html
- https://www.sec4check.pl/blog/posts/cve-formbricks-broken-access-control-stored-xss-custom-head-scripts.html