CVE-2026-44549CWE-79

Open WebUI: Stored XSS in excel file preview

High · published May 15, 2026

CVSS v3.1
7.3
EPSS
0%
Percentile
30.0
In the wild
Unconfirmed
What it is

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.8.0, Excel file attachments are previewed in an unsafe way. A crafted XLSX file payload can be used to cause the sheetjs function sheet_to_html to embed an XSS payload into the generated HTML. This is subsequently added to the DOM unsanitized via @html causing the payload to trigger. This vulnerability is fixed in 0.8.0.

The record
Technical detail
CVSS v3.1
7.3 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00372 · 30.0th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-05-15T21:45Z
EPSS history
Timeline
  • 15 MAY 21:45Z
    Open WebUI: Stored XSS in excel file preview
    cvelistv5