Vulnerability · Published Oct 12, 2026 · Assigned by VulnCheck

CVE-2026-109299Open WebUI 0.9.0 before 0.11.4 Denial of Service via Recurrence Rule Validation

Medium 6.5

In plain English

A medium-severity uncontrolled resource consumption in open-webui from open-webui. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium

Exploit odds (30 days)0.4%top 68.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
open-webui	open-webui	0.9.0 – before 0.11.4

Weakness: CWE-400, CWE-834 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

GitHub Security Advisory (GHSA-5w58-mwmh-vf2m) vendor-advisory
Patch Commit patch
VulnCheck Advisory: Open WebUI 0.9.0 before 0.11.4 Denial of Service via Recurrence Rule Validation third-party-advisory