CVE-2026-109298

Description

Open WebUI 0.11.0 before 0.11.4 compiles user-chosen grep patterns for its knowledge and chat file search tools with a regex engine that expands nested counted repetition unbounded at compile time and caches the result. Authenticated users can have the model call grep_knowledge_files with short nested-repetition patterns, blocking the event loop and exhausting worker memory.

References

• https://github.com/open-webui/open-webui/commit/97e013a66169c4fcd7f26ab9e41a4ff260ffd4da
• https://github.com/open-webui/open-webui/security/advisories/GHSA-gww9-mhgj-pfqh
• https://www.vulncheck.com/advisories/open-webui-0.11.0-before-0.11.4-memory-exhaustion-via-knowledge-search-regex