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… (CVE-2026-109299)

The Open WebUI software versions 0.9.0 before 0.11.4 are vulnerable to a denial of service (DoS) attack. Authenticated users who have automations permission can exploit this vulnerability by sending unsatisfiable recurrence rules repeatedly to the automations create or update endpoints. These invalid rules cause the shared event loop to be blocked for seconds per request, effectively stalling the instance and causing a DoS condition. The CVSS v3.1 base score is 6.5, reflecting a high severity impact with network attack vector, low attack complexity, and requiring privileges but no user interaction.

The vulnerability allows authenticated users with automations permission to cause a denial of service by stalling the Open WebUI instance. This results in service disruption due to the blocking of the shared event loop for multiple seconds per malicious request. There is no impact on confidentiality or integrity, only availability is affected.

A fix is available in Open WebUI version 0.11.4. Users should upgrade to version 0.11.4 or later to remediate this vulnerability. Until patched, restrict automations permission to trusted users only to reduce risk.