CVE-2026-44556 json
Open WebUI: responses passthrough endpoint lacks access control authorization
published 6mo ago modified 3mo ago also EUVD-2026-30624 , GHSA-hp5m-24vp-vq2q , PYSEC-2026-2734
- cvss
- 7.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the /responses endpoint in the OpenAI router accepts any authenticated user and forwards requests directly to upstream LLM providers without enforcing per-model access control. While the primary chat completion endpoint (generate_chat_completion) checks model ownership, group membership, and AccessGrants before allowing a request, the /responses proxy only validates that the user has a valid session via get_verified_user. This allows any authenticated user to interact with any model configured on the instance by sending a POST request to /api/openai/responses with an arbitrary model ID. This vulnerability is fixed in 0.9.0.
Patch / fix
- pypi open-webui 0.9.0
- openwebui open_webui 0.9.0
- github.com/open-webui/open-webui#23481 pull request
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H |
| GitHub | 3.1 | 7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H |
| OSV | 3.1 | 7.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | open-webui | <0.9.0 |
0.9.0 |
Affected products
- open-webui open-webui
Classification
References
-
github.com
/open-webui/open-webui/pull/23481
web
-
github.com
/open-webui/open-webui/security/advisories/GHSA-hp5m-24vp-vq2q
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-44556
advisory
-
github.com
/open-webui/open-webui
package
-
pypi.org
/project/open-webui
package
-
github.com
/advisories/GHSA-hp5m-24vp-vq2q
advisory
Sources
- CVE List CVE-2026-44556
- GitHub Advisory GHSA-hp5m-24vp-vq2q
- NVD CVE-2026-44556
- OSV PYSEC-2026-2734
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.