Vulnerability in Open-Webui
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.
Vulnerability class: ReDoS (Regular Expression Denial of Service)
Published .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/open-webui/open-webui/security/advisories/GHSA-gfjp-5hc9-852r (vendor-advisory)
- www.vulncheck.com/advisories/open-webui-0.11.0-before-0.11.4-redos-via-grep-kno… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109295?
- CVE-2026-109295 is a medium-severity vulnerability in Open-Webui, classified under Inefficient Regular Expression Complexity. CVSS score: 6.5/10. Published 2026-10-12.
- How severe is CVE-2026-109295?
- Medium severity. CVSS v3 base score is 6.5 out of 10.