CVE-2026-109290CWE-1021CWE-79cross-site-scripting

CVE-2026-109290

High · published October 12, 2026

CVSS v3.1
8.7
EPSS
0%
Percentile
16.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.7 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
CVSS v4.0
8.4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
EPSS
0.00255 · 16.2th percentile
Weaknesses
CWE-1021 · Improper Restriction of Rendered UI Layers or Frames; CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-10-12T21:17Z
References (3)
https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg · [email protected]https://www.vulncheck.com/advisories/open-webui-0.11.1-before-0.11.4-stored-xss-via-docx-preview · [email protected]https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 14 OCT 03:27Z
    EPSS moved — → 0%
    epss
  • 12 OCT 16:04Z
    Open WebUI 0.11.1 before 0.11.4 Stored XSS via DOCX Preview
    cvelistv5
  • 12 OCT 16:04Z
    Open WebUI 0.11.1 before 0.11.4 Stored XSS via DOCX Preview
    cvelistv5