CVE-2026-109299

Open WebUI from 0.9.0 before 0.11.4 contains a denial of service vulnerability that allows authenticated users with automations permission to stall the instance by submitting unsatisfiable recurrence rules. Attackers can repeatedly send rules like February 30th to the automations create or update endpoints, blocking the shared event loop for seconds per request.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/commit/5fb869db221d9599a576e8e2eea9c3314947d25e
https://github.com/open-webui/open-webui/security/advisories/GHSA-5w58-mwmh-vf2m
https://www.vulncheck.com/advisories/open-webui-0.9.0-before-0.11.4-denial-of-service-via-recurrence-rule-validation

Configurations

No configuration.

History

23 Oct 2026, 22:16

Type	Values Removed	Values Added
CWE		CWE-834

12 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 17:17

Updated : 2026-10-23 22:16

NVD link : CVE-2026-109299

Mitre link : CVE-2026-109299

CVE.ORG link : CVE-2026-109299

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-834

Excessive Iteration

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