Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.7 · CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N

EPSS

• CVE-2026-59216: 0.45% estimated exploitation activity in the next 30 days; percentile 39.48 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary An authenticated low-privilege user can execute arbitrary code-interpreter Python and tools inside another user's authenticated session. The Socket.IO event-caller (geteventcall) delivers execute:python / execute:tool events to a client-supplied sessionid 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). Affected component - backend/openwebui/socket/main.py — geteventcall() / eventcaller - backend/openwebui/main.py — chat-completion metadata (sessionid taken from…

Published by the source

24 Jul 2026, 17:01 UTC

Last modified by the source

4 Aug 2026, 14:40 UTC

Source last checked

26 Oct 2026, 13:49 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-74h3-cxq7-vc5q

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-74h3-cxq7-vc5q

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# Patch Next advisory brief: CVE-2026-59216

Advisory: Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id
IDs: CVE-2026-59216, GHSA-74h3-cxq7-vc5q
Record: https://patchnext.com/advisories/cve-2026-59216 (revision 2, source checked 26 Oct 2026, 13:49 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: open-webui 0.10.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI open-webui: affected < 0.10.0; fixed in 0.10.0

## Suggested inspection (read-only)
- `python -m pip show open-webui`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on open-webui.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-74h3-cxq7-vc5q (OSV record GHSA-74h3-cxq7-vc5q lists affected ranges: PyPI open-webui >=0 <0.10.0 (fixed))
- Verified: https://github.com/advisories/GHSA-74h3-cxq7-vc5q (GitHub-reviewed advisory GHSA-74h3-cxq7-vc5q lists affected ranges: PyPI open-webui >=0 <0.10.0)

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