{"id":"CVE-2026-59216","aliases":["EUVD-2026-42627","GHSA-74h3-cxq7-vc5q","PYSEC-2026-3592"],"status":"published","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, get_event_call delivered execute:python and execute:tool Socket.IO events to a client-supplied session_id after checking only that the session was connected, allowing authenticated users who learned another socket ID through ydoc:document:join to run code interpreter Python or tools in that user session. This issue is fixed in version 0.10.0.","severity":{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00454,"percentile":0.39738,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-200","CWE-639","CWE-862","CWE-94"],"published":"2026-07-09T16:48:55Z","modified":"2026-10-28T02:30:58Z","fixes":[{"ecosystem":"PyPI","package":"open-webui","fixed_in":["0.10.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.10.0"}]}]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.10.0"}]}],"versions":["0.1.124","0.1.125","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.3.1","0.3.10","0.3.12","0.3.13","0.3.14","0.3.15","0.3.16","0.3.17","0.3.17.dev2","0.3.17.dev3","0.3.17.dev4","0.3.17.dev5","0.3.18","0.3.19","0.3.2","0.3.20","0.3.21","0.3.22","0.3.23","0.3.24","0.3.25","0.3.26","0.3.27","0.3.27.dev1","0.3.27.dev2","0.3.27.dev3","0.3.28","0.3.29","0.3.3","0.3.30","0.3.30.dev1","0.3.30.dev2","0.3.31","0.3.31.dev1","0.3.32","0.3.33","0.3.33.dev1","0.3.34","0.3.35","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9","0.4.0","0.4.0.dev1","0.4.0.dev2","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5","0.4.6","0.4.6.dev1","0.4.7","0.4.8","0.5.0","0.5.0.dev1","0.5.0.dev2","0.5.1","0.5.10","0.5.11","0.5.12","0.5.13","0.5.14","0.5.15","0.5.16","0.5.17","0.5.18","0.5.19","0.5.2","0.5.20","0.5.3","0.5.3.dev1","0.5.4","0.5.5","0.5.6","0.5.7","0.5.8","0.5.9","0.6.0","0.6.1","0.6.10","0.6.11","0.6.12","0.6.13","0.6.14","0.6.15","0.6.16","0.6.18","0.6.19","0.6.2","0.6.20","0.6.21","0.6.22","0.6.23","0.6.24","0.6.25","0.6.26","0.6.26.dev1","0.6.27","0.6.28","0.6.29","0.6.3","0.6.30","0.6.31","0.6.32","0.6.33","0.6.34","0.6.35","0.6.36","0.6.37","0.6.38","0.6.39","0.6.4","0.6.40","0.6.41","0.6.42","0.6.43","0.6.5","0.6.6","0.6.6.dev1","0.6.7","0.6.8","0.6.9","0.7.0","0.7.1","0.7.2","0.8.0","0.8.1","0.8.10","0.8.11","0.8.12","0.8.2","0.8.3","0.8.4","0.8.5","0.8.6","0.8.7","0.8.8","0.8.9","0.9.0","0.9.1","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6"]},{"source":"osv","ecosystem":"PyPI","package":"open-webui","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.10.0"}]}],"versions":["0.1.124","0.1.125","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.3.1","0.3.10","0.3.12","0.3.13","0.3.14","0.3.15","0.3.16","0.3.17","0.3.17.dev2","0.3.17.dev3","0.3.17.dev4","0.3.17.dev5","0.3.18","0.3.19","0.3.2","0.3.20","0.3.21","0.3.22","0.3.23","0.3.24","0.3.25","0.3.26","0.3.27","0.3.27.dev1","0.3.27.dev2","0.3.27.dev3","0.3.28","0.3.29","0.3.3","0.3.30","0.3.30.dev1","0.3.30.dev2","0.3.31","0.3.31.dev1","0.3.32","0.3.33","0.3.33.dev1","0.3.34","0.3.35","0.3.4","0.3.5","0.3.6","0.3.7","0.3.8","0.3.9","0.4.0","0.4.0.dev1","0.4.0.dev2","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5","0.4.6","0.4.6.dev1","0.4.7","0.4.8","0.5.0","0.5.0.dev1","0.5.0.dev2","0.5.1","0.5.10","0.5.11","0.5.12","0.5.13","0.5.14","0.5.15","0.5.16","0.5.17","0.5.18","0.5.19","0.5.2","0.5.20","0.5.3","0.5.3.dev1","0.5.4","0.5.5","0.5.6","0.5.7","0.5.8","0.5.9","0.6.0","0.6.1","0.6.10","0.6.11","0.6.12","0.6.13","0.6.14","0.6.15","0.6.16","0.6.18","0.6.19","0.6.2","0.6.20","0.6.21","0.6.22","0.6.23","0.6.24","0.6.25","0.6.26","0.6.26.dev1","0.6.27","0.6.28","0.6.29","0.6.3","0.6.30","0.6.31","0.6.32","0.6.33","0.6.34","0.6.35","0.6.36","0.6.37","0.6.38","0.6.39","0.6.4","0.6.40","0.6.41","0.6.42","0.6.43","0.6.5","0.6.6","0.6.6.dev1","0.6.7","0.6.8","0.6.9","0.7.0","0.7.1","0.7.2","0.8.0","0.8.1","0.8.10","0.8.11","0.8.12","0.8.2","0.8.3","0.8.4","0.8.5","0.8.6","0.8.7","0.8.8","0.8.9","0.9.0","0.9.1","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6"]}],"products":[{"vendor":"open-webui","product":"open-webui"},{"vendor":"openwebui","product":"open_webui"}],"references":[{"url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-74h3-cxq7-vc5q","tags":["x_refsource_CONFIRM","exploit","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://github.com/open-webui/open-webui/pull/25763","tags":["x_refsource_MISC","Issue Tracking","Patch","fix","web"]},{"url":"https://github.com/open-webui/open-webui/commit/386ac958144dbbbf0aa6e268070d72b681a318aa","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/open-webui/open-webui/releases/tag/v0.10.0","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59216","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-74h3-cxq7-vc5q","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59216.json","tags":["advisory"]},{"url":"https://github.com/open-webui/open-webui","tags":["package"]},{"url":"https://pypi.org/project/open-webui","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-59216","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, get_event_call delivered execute:python and execute:tool Socket.IO events to a client-supplied session_id after checking only that the session was connected, allowing authenticated users who learned another socket ID through ydoc:document:join to run code interpreter Python or tools in that user session. This issue is fixed in version 0.10.0.","status":"published","published":"2026-07-09T16:48:55.663Z","modified":"2026-07-10T03:55:47.517Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-94","CWE-200","CWE-639","CWE-862"],"updated_at":"2026-11-02T14:19:58.944663Z"}],"euvd":[{"id":"EUVD-2026-42627","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, get_event_call delivered execute:python and execute:tool Socket.IO events to a client-supplied session_id after checking only that the session was connected, allowing authenticated users who learned another socket ID through ydoc:document:join to run code interpreter Python or tools in that user session. This issue is fixed in version 0.10.0.","status":"published","published":"2026-07-09T16:48:55Z","modified":"2026-07-10T03:55:47Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T18:20:03.345658Z"}],"ghsa":[{"id":"GHSA-74h3-cxq7-vc5q","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"## Summary\n\nAn authenticated low-privilege user can execute arbitrary code-interpreter Python and tools inside **another** user's authenticated session. The Socket.IO event-caller (`get_event_call`) delivers `execute:python` / `execute:tool` events to a **client-supplied** `session_id` after only checking that the session is connected, never that it belongs to the requester. Combined with `ydoc:document:join`, which exposes the live socket ids of everyone in a shared note's collaboration room to any read-access participant, an attacker can target a victim's session and run attacker-chosen code/tools in the victim's browser context. When the victim is an administrator, that hijacked context reaches the admin-only Functions API, whose source is executed server-side, yielding remote code execution as the server process (root in the default container).\n\n## Affected component\n\n- `backend/open_webui/socket/main.py` — `get_event_call()` / `__event_caller__`\n- `backend/open_webui/main.py` — chat-completion metadata (`session_id` taken from the request body)\n\n## Root cause\n\nThe event-caller routes to a caller-controlled session id with no ownership check:\n\n```python\n# backend/open_webui/socket/main.py — get_event_call()\nasync def __event_caller__(event_data):\n    session_id = request_info['session_id']\n    if session_id not in SESSION_POOL:                 # only checks the session is connected\n        return {'error': 'Client session disconnected.'}\n    return await sio.call('events', {...}, to=session_id, ...)   # delivered to that sid\n```\n\n`session_id` originates from the request body and is never validated against the authenticated user:\n\n```python\n# backend/open_webui/main.py\nmetadata = {\n    'user_id': user.id,                               # server-derived (trustworthy)\n    'session_id': form_data.pop('session_id', None),  # client-controlled\n    ...\n}\n```\n\n`SESSION_POOL[session_id]` is the user record of whoever owns that socket. Because the caller checks only membership (`in SESSION_POOL`), a request carrying another user's `session_id` causes `execute:python` / `execute:tool` to be delivered to that other user's browser.\n\n## Reachability\n\n- `execute:python` / `execute:tool` are emitted from the code-interpreter and tool-call paths (`utils/middleware.py`, `tools/builtin.py`), all routed through `get_event_call`.\n- The victim's live `session_id` is disclosed to any read-access participant of a shared note via `ydoc:document:join`.\n- `POST /api/v1/chat/completions` requires only `get_verified_user` (the default user role). The attacker uses their own account and a model / Direct Connection they control to choose the payload.\n\n## Impact\n\n- **Any victim:** arbitrary code-interpreter Python and tool execution in the victim's authenticated session — the attacker acts with the victim's identity and origin (full session/account compromise).\n- **Admin victim:** the hijacked admin context reaches `POST /api/v1/functions/create`, whose source is `exec()`'d server-side → remote code execution as the server process (root in the default container).\n\nThe Functions API is intended administrator code-execution; the vulnerability here is the cross-user delivery that lets an attacker drive another user's session — including an admin's — into it. The primitive is a full session compromise even against non-admin victims.\n\n## Proof of Concept\n\nThe reporter's `exploit.py` reproduced on `ghcr.io/open-webui/open-webui:0.9.6` and a build of the `v0.9.6` tag, confirming blind server-side RCE out-of-band (callback returns `uid=0(root)`), using only a low-privilege `user` account that shared a note with an admin victim. Preconditions: code interpreter enabled; attacker shares a note with the victim; victim opens it while online; admin victim required for server RCE.\n\n## Fix\n\n`get_event_call` must verify the target session belongs to the requesting user before delivering, not merely that it is connected:\n\n```python\nsession = SESSION_POOL.get(session_id)\nif session is None or session.get('id') != request_info.get('user_id'):\n    return {'error': 'Client session disconnected.'}\n```\n\n`user_id` in the request metadata is server-derived from the authenticated user, so it is trustworthy. Restricting `ydoc:document:join` so it does not disclose other participants' socket ids is recommended as defence-in-depth.\n\n## Affected / Patched\n\n- Affected: `\u003c 0.10.0` (last affected release 0.9.6)\n- Patched: v0.10.0. `get_event_call` now verifies the target session belongs to the requesting user before delivering (`session is None or session.get('id') != request_info.get('user_id')`), using the server-derived `user_id` from the request metadata. The recommended `ydoc:document:join` sid-disclosure restriction is defence-in-depth and independent of this fix; the ownership check closes the cross-user delivery regardless of whether the victim's sid is known.","status":"published","published":"2026-07-24T17:01:53Z","modified":"2026-07-24T17:01:54Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-94","CWE-200","CWE-639","CWE-862"],"updated_at":"2026-11-02T14:40:52.46233Z"}],"nvd":[{"id":"CVE-2026-59216","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, get_event_call delivered execute:python and execute:tool Socket.IO events to a client-supplied session_id after checking only that the session was connected, allowing authenticated users who learned another socket ID through ydoc:document:join to run code interpreter Python or tools in that user session. This issue is fixed in version 0.10.0.","status":"published","published":"2026-07-09T17:17:02.467Z","modified":"2026-07-13T12:24:30.137Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":9,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","level":"critical","assessor":"primary"}],"cwes":["CWE-94","CWE-200","CWE-639","CWE-862"],"updated_at":"2026-11-02T14:12:28.4135Z"}],"osv":[{"id":"CVE-2026-59216","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. Prior to 0.10.0, get_event_call delivered execute:python and execute:tool Socket.IO events to a client-supplied session_id after checking only that the session was connected, allowing authenticated users who learned another socket ID through ydoc:document:join to run code interpreter Python or tools in that user session. This issue is fixed in version 0.10.0.","status":"published","published":"2026-07-09T16:48:55.663Z","modified":"2026-10-28T02:30:58.632641545Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-200","CWE-639","CWE-862","CWE-94"],"updated_at":"2026-11-02T15:45:12.496548Z"},{"id":"GHSA-74h3-cxq7-vc5q","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"## Summary\n\nAn authenticated low-privilege user can execute arbitrary code-interpreter Python and tools inside **another** user's authenticated session. The Socket.IO event-caller (`get_event_call`) delivers `execute:python` / `execute:tool` events to a **client-supplied** `session_id` after only checking that the session is connected, never that it belongs to the requester. Combined with `ydoc:document:join`, which exposes the live socket ids of everyone in a shared note's collaboration room to any read-access participant, an attacker can target a victim's session and run attacker-chosen code/tools in the victim's browser context. When the victim is an administrator, that hijacked context reaches the admin-only Functions API, whose source is executed server-side, yielding remote code execution as the server process (root in the default container).\n\n## Affected component\n\n- `backend/open_webui/socket/main.py` — `get_event_call()` / `__event_caller__`\n- `backend/open_webui/main.py` — chat-completion metadata (`session_id` taken from the request body)\n\n## Root cause\n\nThe event-caller routes to a caller-controlled session id with no ownership check:\n\n```python\n# backend/open_webui/socket/main.py — get_event_call()\nasync def __event_caller__(event_data):\n    session_id = request_info['session_id']\n    if session_id not in SESSION_POOL:                 # only checks the session is connected\n        return {'error': 'Client session disconnected.'}\n    return await sio.call('events', {...}, to=session_id, ...)   # delivered to that sid\n```\n\n`session_id` originates from the request body and is never validated against the authenticated user:\n\n```python\n# backend/open_webui/main.py\nmetadata = {\n    'user_id': user.id,                               # server-derived (trustworthy)\n    'session_id': form_data.pop('session_id', None),  # client-controlled\n    ...\n}\n```\n\n`SESSION_POOL[session_id]` is the user record of whoever owns that socket. Because the caller checks only membership (`in SESSION_POOL`), a request carrying another user's `session_id` causes `execute:python` / `execute:tool` to be delivered to that other user's browser.\n\n## Reachability\n\n- `execute:python` / `execute:tool` are emitted from the code-interpreter and tool-call paths (`utils/middleware.py`, `tools/builtin.py`), all routed through `get_event_call`.\n- The victim's live `session_id` is disclosed to any read-access participant of a shared note via `ydoc:document:join`.\n- `POST /api/v1/chat/completions` requires only `get_verified_user` (the default user role). The attacker uses their own account and a model / Direct Connection they control to choose the payload.\n\n## Impact\n\n- **Any victim:** arbitrary code-interpreter Python and tool execution in the victim's authenticated session — the attacker acts with the victim's identity and origin (full session/account compromise).\n- **Admin victim:** the hijacked admin context reaches `POST /api/v1/functions/create`, whose source is `exec()`'d server-side → remote code execution as the server process (root in the default container).\n\nThe Functions API is intended administrator code-execution; the vulnerability here is the cross-user delivery that lets an attacker drive another user's session — including an admin's — into it. The primitive is a full session compromise even against non-admin victims.\n\n## Proof of Concept\n\nThe reporter's `exploit.py` reproduced on `ghcr.io/open-webui/open-webui:0.9.6` and a build of the `v0.9.6` tag, confirming blind server-side RCE out-of-band (callback returns `uid=0(root)`), using only a low-privilege `user` account that shared a note with an admin victim. Preconditions: code interpreter enabled; attacker shares a note with the victim; victim opens it while online; admin victim required for server RCE.\n\n## Fix\n\n`get_event_call` must verify the target session belongs to the requesting user before delivering, not merely that it is connected:\n\n```python\nsession = SESSION_POOL.get(session_id)\nif session is None or session.get('id') != request_info.get('user_id'):\n    return {'error': 'Client session disconnected.'}\n```\n\n`user_id` in the request metadata is server-derived from the authenticated user, so it is trustworthy. Restricting `ydoc:document:join` so it does not disclose other participants' socket ids is recommended as defence-in-depth.\n\n## Affected / Patched\n\n- Affected: `\u003c 0.10.0` (last affected release 0.9.6)\n- Patched: v0.10.0. `get_event_call` now verifies the target session belongs to the requesting user before delivering (`session is None or session.get('id') != request_info.get('user_id')`), using the server-derived `user_id` from the request metadata. The recommended `ydoc:document:join` sid-disclosure restriction is defence-in-depth and independent of this fix; the ownership check closes the cross-user delivery regardless of whether the victim's sid is known.","status":"published","published":"2026-07-24T17:01:53Z","modified":"2026-08-04T14:40:53.077303916Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-200","CWE-639","CWE-862","CWE-94"],"updated_at":"2026-11-02T15:46:40.308826Z"},{"id":"PYSEC-2026-3592","title":"Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id","description":"## Summary\n\nAn authenticated low-privilege user can execute arbitrary code-interpreter Python and tools inside **another** user's authenticated session. The Socket.IO event-caller (`get_event_call`) delivers `execute:python` / `execute:tool` events to a **client-supplied** `session_id` after only checking that the session is connected, never that it belongs to the requester. Combined with `ydoc:document:join`, which exposes the live socket ids of everyone in a shared note's collaboration room to any read-access participant, an attacker can target a victim's session and run attacker-chosen code/tools in the victim's browser context. When the victim is an administrator, that hijacked context reaches the admin-only Functions API, whose source is executed server-side, yielding remote code execution as the server process (root in the default container).\n\n## Affected component\n\n- `backend/open_webui/socket/main.py` — `get_event_call()` / `__event_caller__`\n- `backend/open_webui/main.py` — chat-completion metadata (`session_id` taken from the request body)\n\n## Root cause\n\nThe event-caller routes to a caller-controlled session id with no ownership check:\n\n```python\n# backend/open_webui/socket/main.py — get_event_call()\nasync def __event_caller__(event_data):\n    session_id = request_info['session_id']\n    if session_id not in SESSION_POOL:                 # only checks the session is connected\n        return {'error': 'Client session disconnected.'}\n    return await sio.call('events', {...}, to=session_id, ...)   # delivered to that sid\n```\n\n`session_id` originates from the request body and is never validated against the authenticated user:\n\n```python\n# backend/open_webui/main.py\nmetadata = {\n    'user_id': user.id,                               # server-derived (trustworthy)\n    'session_id': form_data.pop('session_id', None),  # client-controlled\n    ...\n}\n```\n\n`SESSION_POOL[session_id]` is the user record of whoever owns that socket. Because the caller checks only membership (`in SESSION_POOL`), a request carrying another user's `session_id` causes `execute:python` / `execute:tool` to be delivered to that other user's browser.\n\n## Reachability\n\n- `execute:python` / `execute:tool` are emitted from the code-interpreter and tool-call paths (`utils/middleware.py`, `tools/builtin.py`), all routed through `get_event_call`.\n- The victim's live `session_id` is disclosed to any read-access participant of a shared note via `ydoc:document:join`.\n- `POST /api/v1/chat/completions` requires only `get_verified_user` (the default user role). The attacker uses their own account and a model / Direct Connection they control to choose the payload.\n\n## Impact\n\n- **Any victim:** arbitrary code-interpreter Python and tool execution in the victim's authenticated session — the attacker acts with the victim's identity and origin (full session/account compromise).\n- **Admin victim:** the hijacked admin context reaches `POST /api/v1/functions/create`, whose source is `exec()`'d server-side → remote code execution as the server process (root in the default container).\n\nThe Functions API is intended administrator code-execution; the vulnerability here is the cross-user delivery that lets an attacker drive another user's session — including an admin's — into it. The primitive is a full session compromise even against non-admin victims.\n\n## Proof of Concept\n\nThe reporter's `exploit.py` reproduced on `ghcr.io/open-webui/open-webui:0.9.6` and a build of the `v0.9.6` tag, confirming blind server-side RCE out-of-band (callback returns `uid=0(root)`), using only a low-privilege `user` account that shared a note with an admin victim. Preconditions: code interpreter enabled; attacker shares a note with the victim; victim opens it while online; admin victim required for server RCE.\n\n## Fix\n\n`get_event_call` must verify the target session belongs to the requesting user before delivering, not merely that it is connected:\n\n```python\nsession = SESSION_POOL.get(session_id)\nif session is None or session.get('id') != request_info.get('user_id'):\n    return {'error': 'Client session disconnected.'}\n```\n\n`user_id` in the request metadata is server-derived from the authenticated user, so it is trustworthy. Restricting `ydoc:document:join` so it does not disclose other participants' socket ids is recommended as defence-in-depth.\n\n## Affected / Patched\n\n- Affected: `\u003c 0.10.0` (last affected release 0.9.6)\n- Patched: v0.10.0. `get_event_call` now verifies the target session belongs to the requesting user before delivering (`session is None or session.get('id') != request_info.get('user_id')`), using the server-derived `user_id` from the request metadata. The recommended `ydoc:document:join` sid-disclosure restriction is defence-in-depth and independent of this fix; the ownership check closes the cross-user delivery regardless of whether the victim's sid is known.","status":"published","published":"2026-08-04T11:34:42.837663Z","modified":"2026-08-04T14:30:29.928000066Z","cvss":[{"version":"3.1","score":7.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:56.847083Z"}]}}