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Open WebuiApplication · Openwebui

CVE-2026-56400

CRITICAL · 9.6 CVSS v3.1 Published 2026-07-15
Fix available
A fix is available. Upgrade to 0.3.14 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges 5 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
open-webui before 0.3.14 contains a cross-origin resource sharing misconfiguration allowing arbitrary origins with allow_origins=* and authenticated requests to the /api/v1/functions endpoint. Attackers can execute arbitrary code on the openwebui instance by crafting malicious cross-site requests from attacker-controlled websites when an admin user visits them.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

open-webui before 0.3.14 has a CORS misconfiguration on the /api/v1/functions endpoint that allows requests from any origin (allow_origins=*) while still accepting authenticated requests. Attackers can exploit this by tricking an authenticated admin into visiting a malicious website, which then sends cross-origin requests to execute arbitrary code on the open-webui instance.

MitigationUpgrade open-webui to version 0.3.14 or later, or configure CORS to whitelist specific trusted origins instead of using the wildcard (*) on sensitive endpoints.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Open WebuiApplication
Affected:< 0.3.14

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Open WebUI installation and version
    Locate the open-webui installation and check its version file (e.g., package.json, VERSION file, or docker image tag). If using Docker, run 'docker images | grep open-webui' to see the image tag.
    Affected if The installed version is earlier than 0.3.14 (e.g., 0.3.13, 0.3.12, etc.)
  2. Inspect CORS configuration for /api/v1/functions endpoint
    Review the source code or configuration files for CORS settings. Look for allow_origins, allow_credentials, and similar CORS-related configuration in the web application code or server configuration.
    Affected if The CORS configuration for /api/v1/functions shows allow_origins set to '*' (wildcard) or contains no origin whitelist
  3. Test CORS headers on the affected endpoint
    Send an HTTP request to /api/v1/functions with an Origin header set to an arbitrary domain (e.g., 'Origin: https://malicious-site.com'). Inspect the response headers for Access-Control-Allow-Origin.
    Affected if The response includes 'Access-Control-Allow-Origin: *' or echoes back the arbitrary origin, indicating wildcard or unsafe origin handling
  4. Verify authentication is accepted with cross-origin requests
    With the CORS test above, also include valid authentication credentials (cookies, tokens) in the cross-origin request. Check if the request is processed as an authenticated request.
    Affected if Authenticated requests from arbitrary origins are accepted and processed by the /api/v1/functions endpoint

A user is affected if their Open WebUI version is earlier than 0.3.14 AND the /api/v1/functions endpoint accepts cross-origin requests with the wildcard origin (*) while still processing authenticated requests.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 0.3.14 or later
Fixed in 0.3.14
Interim mitigation

Upgrade open-webui to version 0.3.14 or later, or configure CORS to whitelist specific trusted origins instead of using the wildcard (*) on sensitive endpoints.

Recommended fix High confidence

0.3.14 or later

  1. 1. Upgrade Open Webui to version 0.3.14 or later by pulling the latest container image or using your deployment method (e.g., docker pull your-registry/open-webui:latest or pip install --upgrade open-webui)
  2. 2. Restart the Open Webui service to apply the update
  3. 3. Verify the upgrade was successful by checking the version number in the application UI or logs
  4. 4. Confirm the CORS configuration no longer allows arbitrary origins by reviewing the backend configuration files

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Open Webui Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
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An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-56400 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data