CVE-2026-88000
Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, DELETE /api/v1/chats/{id}/messages/{message_id} used the chat-history deletion helper in backend/open_webui/models/chats.py to follow childrenIds without recording visited message identifiers. An authenticated user could store a cyclic chat tree and delete a message, causing a synchronous infinite loop on the server request loop that blocked every user's requests until the process was killed. This issue is fixed in version 0.11.1.
| CWE | CWE-835 |
| Vendor | open-webui |
| Product | open-webui |
| Published | Sep 9, 2026 |
| Last Updated | Sep 10, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
open-webui / open-webui
>= 0.10.0, < 0.11.1
References
github.com: https://github.com/open-webui/open-webui/security/advisories/GHSA-3cgp-3cqx-j8w2 github.com: https://github.com/open-webui/open-webui/pull/28035 github.com: https://github.com/open-webui/open-webui/commit/b933292d63d12be3fd1416fe55519ddc7aa336bc github.com: https://github.com/open-webui/open-webui/releases/tag/v0.11.1