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...

Open WebUI: Any authenticated user can hang the server via a cyclic chat message history

Summary Chat histories are stored as an unvalidated JSON object. The walk that reconstructs a chat's message chain detected repeats using each message's own id field while moving through the history by map key, so a message that simply omitted id was never recorded as visited. A history whose...

EUVD-2026-75188

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

GHSA-JQHH-CJMQ-VMV6 Open WebUI: Any authenticated user can hang the server via a cyclic chat message history

Summary Chat histories are stored as an unvalidated JSON object. The walk that reconstructs a chat's message chain detected repeats using each message's own id field while moving through the history by map key, so a message that simply omitted id was never recorded as visited. A history whose...

CVE-2026-88002

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.1, the message-chain reconstruction helper in backend/openwebui/utils/misc.py advanced through a chat history by map key but tracked visited entries using each message body's optional id...

CVE-2026-88000

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/messageid used the chat-history deletion helper in backend/openwebui/models/chats.py to follow childrenIds without recording visited message identifiers...

CVE-2026-88002

Open WebUI (self-hosted AI platform), versions 0.5.0 through 0.11.1 , is affected by a denial-of-service vulnerability in the message-chain reconstruction helper in backend/open_webui/utils/misc.py. The helper advanced through chat history by map key but tracked visited entries using each message...

CVE-2026-88002 Open WebUI: Any authenticated user can hang the server via a cyclic chat message history

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.1, the message-chain reconstruction helper in backend/openwebui/utils/misc.py advanced through a chat history by map key but tracked visited entries using each message body's optional id...

CVE-2026-88002 Open WebUI: Any authenticated user can hang the server via a cyclic chat message history

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.5.0 until 0.11.1, the message-chain reconstruction helper in backend/openwebui/utils/misc.py advanced through a chat history by map key but tracked visited entries using each message body's optional id...

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...

CVE-2026-88000 Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree

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/messageid used the chat-history deletion helper in backend/openwebui/models/chats.py to follow childrenIds without recording visited message identifiers...

CVE-2026-88000 Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree

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/messageid used the chat-history deletion helper in backend/openwebui/models/chats.py to follow childrenIds without recording visited message identifiers...

CVE-2026-87013

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, POST /api/v1/folders/id/update/parent allowed a user to place a folder under itself or one of its descendants, while the folder tree walks used by DELETE /api/v1/folders/id and POST...

CVE-2026-87011

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...

CVE-2026-87013 Open WebUI: Any authenticated user can start a non-terminating request via a folder parent cycle

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.10.0 until 0.11.1, POST /api/v1/folders/id/update/parent allowed a user to place a folder under itself or one of its descendants, while the folder tree walks used by DELETE /api/v1/folders/id and POST...

CVE-2026-87013

Open WebUI versions 0.10.0 through 0.11.1 contain a denial-of-service vulnerability in the folder tree functionality. The POST /api/v1/folders/{id}/update/parent endpoint allowed an authenticated user to place a folder under itself or one of its descendants, creating a parent cycle . Because the ...

CVE-2026-87011 Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...

CVE-2026-87011

Open WebUI , a self-hosted AI platform, contains a denial-of-service vulnerability in the unauthenticated POST /oauth/backchannel-logout handler (backend/open_webui/utils/oauth.py). From version 0.9.0 through 0.11.1 , the handler fetched the OIDC discovery document and signing keys before validat...

CVE-2026-87011 Open WebUI: Unauthenticated requests can stall the server via uncached OIDC fetches in back-channel logout

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.1, the unauthenticated POST /oauth/backchannel-logout handler in backend/openwebui/utils/oauth.py fetched the OIDC discovery document and signing keys before validating a submitted logout...