CVE-2026-70483 Open WebUI: Any authenticated user can cancel another user's chat generation via the chat delete endpoint
Authenticated users can cancel other users' active AI chat generations by exploiting a missing authorization check in the delete endpoint.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-70483?
CVE-2026-70483 is a low-severity missing authorization vulnerability in Openwebui Open Webui, published on 4 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.6 until 0.11.0, DELETE /api/v1/chats/{id} cancelled a chat's in-flight tasks before checking whether the caller could delete that chat. Any authenticated user who knew another user's chat id could abort that user's running model response, title generation, or tag generation, even though the delete was refused and no chat data was deleted, modified, or disclosed. This issue is fixed in 0.11.0.
Weakness: CWE-862
Which versions are affected by CVE-2026-70483?
3 open source packages ship an affected version, including open-webui. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
open-webui PyPI | From 0.9.6 | 0.11.0 |
open-webui PyPI | From 0.9.6 | 0.11.0 |
open-webui PyPI | From 0.9.6 | 0.11.0 |
Products include Openwebui Open Webui.
How do I fix CVE-2026-70483?
Upgrade open-webui to 0.11.0 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-70483 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-70483 exists.
Other vulnerabilities in Openwebui Open Webui
- CVE-2026-44551 Open WebUI: LDAP Empty Password Authentication Bypass
- CVE-2026-56400 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation
- CVE-2024-8017 Cross-site Scripting (XSS) in open-webui/open-webui
- CVE-2026-45672 Open WebUI: Jupyter code execution works despite `ENABLE_CODE_EXECUTION=false` — feature gate bypassed
- CVE-2026-87995 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin
Sources
Also known as GHSA-3vf6-64vr-3g56, PYSEC-2026-3640.