CVE-2026-109298
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 7.1 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.47% probability · 40th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-400, CWE-770
- Source
- disclosure@vulncheck.com
EPSS moved from 0.4% on 13 October 2026 to 0.5% on 26 October 2026.
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
- https://github.com/open-webui/open-webui/security/advisories/GHSA-gww9-mhgj-pfqh
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.