Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree

Summary Chat histories are stored as an unvalidated JSON object. After a message is deleted, the code that picks the chat's new current message walked down the childrenIds links without recording where it had already been. Any account with the default user role could store a chat whose messages...

GHSA-3CGP-3CQX-J8W2 Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree

Summary Chat histories are stored as an unvalidated JSON object. After a message is deleted, the code that picks the chat's new current message walked down the childrenIds links without recording where it had already been. Any account with the default user role could store a chat whose messages...

EUVD-2026-75185

Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree...

CVE-2026-88000

Open WebUI (a self-hosted AI platform) versions 0.10.0 through 0.11.1 contain a denial-of-service vulnerability in the DELETE /api/v1/chats/{id}/messages/{message_id} endpoint. The chat-history deletion helper follows childrenIds without tracking visited message identifiers, so an authenticated u...