CVE-2026-109297

6.5Medium

Published 12 Oct 2026 · NVD status: Awaiting Analysis · AI triage by gemini-3.8-flash

6.5Medium

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: None
Impact: High impact on availability
Weakness: CWE-400

Impact

Authenticated users allowed to create automations can trigger a persistent denial of service that blocks the shared event loop. They only need access to create automations with crafted recurrence rules.

Root cause

The recurrence-rule validator parses frequency rules more strictly than the execution engine, allowing malformed sub-daily rules to bypass validation and expand synchronously per second.

Affected systems

Open WebUI 0.11.0 before 0.11.4

CVSS v3.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Fix & remediation

Upgrade Open WebUI to version 0.11.4 or later. If you cannot upgrade immediately, revoke automation creation permissions from non-admin users.

shell

$ pip install --upgrade open-webui

AI-suggested. Run it in staging first and check it against the vendor advisory. Why?

Ad · In-content banner

NVD description

Open WebUI 0.11.0 before 0.11.4 contains a denial of service vulnerability in the automation recurrence-rule validator, whose sub-daily frequency guard parses rule text more strictly than the calendar library that executes it. Users permitted to create automations can submit whitespace-folded rules (or, in 0.11.0, lowercase frequencies or omitted RRULE prefixes) that expand per-second synchronously, blocking the shared event loop for minutes per request and on every scheduler poll.

References

Source: nvd.nist.gov/vuln/detail/CVE-2026-109297