CVE-2026-54021 json
Open WebUI: Authenticated users can target arbitrary configured Ollama backends via unguarded url_idx path parameter
published 4mo ago modified 3mo ago also GHSA-9rpj-v7hf-vv2w , PYSEC-2026-2718 , EUVD-2026-38522
- cvss
- 6.3
- 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 21%
- public exploits
- 0
- none known
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6, several direct, index-addressed Ollama proxy routes accept a caller-supplied url_idx path parameter and use it as a raw index into the admin-configured OLLAMA_BASE_URLS list. Access control on these routes validates only whether the user may use the requested model, never which backend the request is routed to. Any authenticated user can append an arbitrary url_idx to force their request onto an Ollama backend they were never authorized to reach, including internal, higher-privilege, or explicitly admin-disabled backends. This vulnerability is fixed in 0.9.6.
Patch / fix
- pypi open-webui 0.9.6
- openwebui open_webui 0.9.6
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4mo ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
| OSV | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
| GitHub | 3.1 | 6.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | open-webui | <0.9.6 |
0.9.6 |
Affected products
- open-webui open-webui
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/open-webui/open-webui/security/advisories/GHSA-9rpj-v7hf-vv2w
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-54021
advisory
-
github.com
/advisories/GHSA-9rpj-v7hf-vv2w
advisory
-
github.com
/open-webui/open-webui
package
-
github.com
/pypa/advisory-database/tree/main/vulns/open-webui/PYSEC-2026-2718.yaml
web
-
pypi.org
/project/open-webui
web, package
Sources
- CVE List CVE-2026-54021
- GitHub Advisory GHSA-9rpj-v7hf-vv2w
- NVD CVE-2026-54021
- OSV PYSEC-2026-2718
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