Open WebUI from 0.11.1 before 0.11.4 contains a stored cross-site scripting vulnerability in DocxPreview.svelte that allows authenticated users to execute script by uploading crafted DOCX attachments. Attackers can embed an OOXML altChunk HTML part or script-scheme hyperlink to steal a previewing administrator's session token from local storage and take over the instance.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-1021",
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/109xxx/CVE-2026-109290.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0.11.1"
},
{
"fixed": "0.11.4"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"introduced": "0.11.1"
},
{
"fixed": "0.11.4"
}
],
"source": "DESCRIPTION"
}
]
}