{"id":"CVE-2026-88000","summary":"Open WebUI: Any authenticated user can hang the server via message deletion in a cyclic chat tree","details":"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.","aliases":["GHSA-3cgp-3cqx-j8w2","PYSEC-2026-3877"],"modified":"2026-09-12T03:30:51.479890883Z","published":"2026-09-09T21:35:25.061Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-835"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/88xxx/CVE-2026-88000.json"},"references":[{"type":"WEB","url":"https://github.com/open-webui/open-webui/releases/tag/v0.11.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/88xxx/CVE-2026-88000.json"},{"type":"ADVISORY","url":"https://github.com/open-webui/open-webui/security/advisories/GHSA-3cgp-3cqx-j8w2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-88000"},{"type":"FIX","url":"https://github.com/open-webui/open-webui/commit/b933292d63d12be3fd1416fe55519ddc7aa336bc"},{"type":"FIX","url":"https://github.com/open-webui/open-webui/pull/28035"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/open-webui/open-webui","events":[{"introduced":"4d2e13cf2bcc451b33bb6374bea4d2163e6cc94c"},{"fixed":"b933292d63d12be3fd1416fe55519ddc7aa336bc"},{"fixed":"d3e8bf3405e848cfba377814d0aa7ba7290e414d"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0.10.0"},{"fixed":"0.11.1"}]}}],"versions":["v0.11.0","v0.10.2","v0.10.1","v0.10.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-88000.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}