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/open_webui/utils/misc.py advanced through a chat history by map key but tracked visited entries using each message body's optional id field. An authenticated user could store id-less messages in a parent cycle and trigger a non-terminating walk that blocked the async event loop, grew memory until termination, and remained persistent across process restarts. This issue is fixed in version 0.11.1.
https://github.com/open-webui/open-webui/security/advisories/GHSA-jqhh-cjmq-vmv6
https://github.com/open-webui/open-webui/releases/tag/v0.11.1
https://github.com/open-webui/open-webui/pull/28034
https://github.com/open-webui/open-webui/commit/5c79ccc9e5c9efc2bc024d8f0b9757652ece929a