CVE-2026-109295

Open WebUI from 0.11.0 before 0.11.4 contains a regular expression denial of service vulnerability that allows authenticated users to stall server workers via file search patterns. Attackers can instruct the model to call grep_knowledge_files or grep_chat_files with a catastrophically backtracking regex, blocking the event loop for two seconds per repeated call.

• https://github.com/open-webui/open-webui/security/advisories/GHSA-gfjp-5hc9-852r
• https://www.vulncheck.com/advisories/open-webui-0.11.0-before-0.11.4-redos-via-grep-knowledge-files-event-loop
• https://github.com/open-webui/open-webui/security/advisories/GHSA-gfjp-5hc9-852r