Memory Exhaustion Vulnerability in Open WebUI by Open WebUI
CVE-2026-109298

7.1HIGH

Key Information:

Vendor

Open-webui

Status
Open-webui
Vendor
CVE Published:
12 October 2026

What is CVE-2026-109298?

A significant issue exists in Open WebUI versions prior to 0.11.4, where the regex engine responsible for processing user-defined grep patterns enables nested counted repetition to be compiled unbounded at runtime. This can lead to authenticated users blocking the event loop and depleting system memory by issuing excessive requests to the grep_knowledge_files model. As a result, the system may become unstable, leading to potential service interruptions.

Affected Version(s)

open-webui 0.11.0 < 0.11.4

open-webui 0.11.4

References

https://github.com/open-webui/open-webui/security/advisor...
vendor-advisory
https://github.com/open-webui/open-webui/commit/97e013a66...
patch
https://www.vulncheck.com/advisories/open-webui-0.11.0-be...
third-party-advisory

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

baeseungwon1010
Classic298
.