CVE-2026-109290

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.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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
https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg

Configurations

No configuration.

History

23 Oct 2026, 22:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~7.3~~	v2 : unknown v3 : 8.7
CWE		CWE-1021

13 Oct 2026, 19:18

Type	Values Removed	Values Added
References	~~() https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg -~~	() https://github.com/open-webui/open-webui/security/advisories/GHSA-f9xp-mfmq-x6cg -

12 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 17:17

Updated : 2026-10-23 22:16

NVD link : CVE-2026-109290

Mitre link : CVE-2026-109290

CVE.ORG link : CVE-2026-109290

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-1021

Improper Restriction of Rendered UI Layers or Frames

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