vulnerability / NVI-00016006 / Revision 1
Open WebUI: Authenticated users can target arbitrary configured Ollama backends via unguarded url_idx path parameter
GitHub lists this reviewed advisory for open-webui. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
6.3 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
open-webui
source listed<= 0.9.5
## Summary 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. ## Affected endpoints All indexed Ollama routes that resolve the backend through `get_ollama_url()`: ``` POST /ollama/api/chat/{url_idx} POST /ollama/api/generate/{url_idx} POST /ollama/api/embed/{url_idx} POST /ollama/api/embeddings/{url_idx} POST /ollama/v1/chat/completions/{url_idx} POST /ollama/v1/completions/{url_idx} POST /ollama/v1/messages/{url_idx} POST /ollama/v1/responses/{url_idx} ``` ## Root cause `backend/open_webui/routers/ollama.py` — `get_ollama_url()` consults the model-to-backend allow-list (`OLLAMA_MODELS[model]["urls"]`) only when `url_idx` is omitted. When the caller supplies `url_idx`, that mapping is skipped and t
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-9rpj-v7hf-vv2w ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.