CVE-2026-109290

HIGH 7.3

Open WebUI 0.11.1 before 0.11.4 Stored XSS via DOCX Preview

CVSS Score

7.3

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-79
Vendor	open-webui
Product	open-webui
Published	Oct 12, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Affected Versions

open-webui / open-webui

0.11.1 < 0.11.4

References

NVD ↗ CVE.org ↗ EPSS Data ↗

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

Credits

🔍 Observerkay Classic298