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.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-400",
"CWE-436"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/109xxx/CVE-2026-109297.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0.11.0"
},
{
"fixed": "0.11.4"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"introduced": "0.11.0"
},
{
"fixed": "0.11.4"
}
],
"source": "DESCRIPTION"
}
]
}