# CVE-2026-44550: Open WebUI: Mass Assignment via Pydantic extra='allow' Allows Creating Folders in Other Users' Accounts

> Attackers can create folders in other users' accounts by injecting user_id fields due to improper Pydantic validation handling.

- **Severity:** Medium 5.0 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 May 2026
- **Updated:** 15 May 2026
- **Also known as:** GHSA-hr43-rjmr-7wmm, PYSEC-2026-2735

## What is CVE-2026-44550?

CVE-2026-44550 is a medium-severity missing authorization vulnerability in Openwebui Open Webui, published on 15 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, FolderForm uses model_config = ConfigDict(extra='allow'), which permits arbitrary fields to pass through Pydantic validation and be included in model_dump(exclude_unset=True). In insert_new_folder, the server-assigned user_id is placed at the start of the dict and then overwritten by the spread of form data. Because FolderModel declares user_id: str as a real field (not just a form extra), any attacker-supplied user_id in the POST body is accepted by the model and persisted on the Folder row. This vulnerability is fixed in 0.9.0.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-44550?

3 open source packages ship an affected version, including open-webui. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `open-webui` | PyPI | All versions | 0.9.0 |
| `open-webui` | PyPI | All versions | 0.9.0 |
| `open-webui` | PyPI | All versions | 0.9.0 |

Products: Openwebui Open Webui.

## How do I fix CVE-2026-44550?

Upgrade open-webui to 0.9.0 or later.

## Is CVE-2026-44550 being exploited?

There is no known exploitation of CVE-2026-44550 in the wild and no public exploit code.

## Other vulnerabilities in Openwebui Open Webui

- [CVE-2026-44551](https://insights.sbomify.com/CVE-2026-44551/): Open WebUI: LDAP Empty Password Authentication Bypass (critical 9.1)
- [CVE-2026-56400](https://insights.sbomify.com/CVE-2026-56400/): open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation (critical 9.0)
- [CVE-2024-8017](https://insights.sbomify.com/CVE-2024-8017/): Cross-site Scripting (XSS) in open-webui/open-webui (critical 9.0)
- [CVE-2026-45672](https://insights.sbomify.com/CVE-2026-45672/): Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed (high 8.8)
- [CVE-2026-87995](https://insights.sbomify.com/CVE-2026-87995/): Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-44550 and fix it if it is affected.

What it is: CVE-2026-44550 is a medium-severity missing authorization vulnerability in Openwebui Open Webui, published on 15 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-44550 in the wild and no public exploit code.

Affected packages and fixed versions:
- open-webui (PyPI): affected all versions; fixed in 0.9.0
- open-webui (PyPI): affected all versions; fixed in 0.9.0
- open-webui (PyPI): affected all versions; fixed in 0.9.0

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-2026-44550/ (Markdown: https://insights.sbomify.com/CVE-2026-44550/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-44550
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-44550
- OSV: https://osv.dev/vulnerability/CVE-2026-44550

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-44550/
Summaries are generated and may contain mistakes; the official description above is the record.