Open WebUI's Mass Assignment via Pydantic extra='allow' Allows Creating Folders in Other Users' Accounts

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.0 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N

EPSS

• CVE-2026-44550: 0.29% estimated exploitation activity in the next 30 days; percentile 21.27 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Mass Assignment via Pydantic extra='allow' Allows Creating Folders in Other Users' Accounts Affected Component Folder creation endpoint and form model: - backend/openwebui/models/folders.py (lines 72-77, FolderForm with extra='allow') - backend/openwebui/models/folders.py (lines 95-106, insertnewfolder dict construction) - backend/openwebui/routers/folders.py (line 119, createfolder endpoint) Affected Versions Current main branch (commit 6fdd19bf1) and likely all versions since FolderForm adopted extra='allow'. Description FolderForm uses modelconfig = ConfigDict(extra='allow'), which permits arbitrary fields to pass through Pydantic validation and be included in modeldump(excludeunset=True). In insertnewfolder, the server-assigned userid is placed at the start of the dict and then overwritten by the spread of form data: Because FolderModel declares userid: str as a real field (not just a form extra), any attacker-supplied userid in the POST body is accepted by the model and…

Published by the source

8 May 2026, 19:38 UTC

Last modified by the source

13 Jul 2026, 16:43 UTC

Source last checked

26 Oct 2026, 13:41 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-hr43-rjmr-7wmm

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-hr43-rjmr-7wmm

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# Patch Next advisory brief: CVE-2026-44550

Advisory: Open WebUI's Mass Assignment via Pydantic extra='allow' Allows Creating Folders in Other Users' Accounts
IDs: CVE-2026-44550, GHSA-hr43-rjmr-7wmm
Record: https://patchnext.com/advisories/cve-2026-44550 (revision 2, source checked 26 Oct 2026, 13:41 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: open-webui 0.9.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI open-webui: affected <= 0.8.12; fixed in 0.9.0

## Suggested inspection (read-only)
- `python -m pip show open-webui`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on open-webui.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-hr43-rjmr-7wmm (OSV record GHSA-hr43-rjmr-7wmm lists affected ranges: PyPI open-webui >=0 <0.9.0 (fixed))
- Verified: https://github.com/advisories/GHSA-hr43-rjmr-7wmm (GitHub-reviewed advisory GHSA-hr43-rjmr-7wmm lists affected ranges: PyPI open-webui >=0 <=0.8.12)

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