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TI-2026-71106 Aliases CVE-2026-109290GHSA-39h3-jjqw-8pch

Stored cross-site scripting in Open WebUI via DOCX preview

Priority HIGH 72CWE-1021Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Active
Attack complexity
Low
Attack requirements
None
Impact type
Spoofing, Cross-site scripting
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-1021 and CWE-79.

Summary

Open WebUI from 0.11.1 before 0.11.4 contains a stored cross-site scripting flaw (CWE-79) in its DOCX preview. An authenticated user can upload a crafted DOCX attachment that runs script when an administrator previews it. The script can steal the administrator's session token from local storage and take over the instance.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00313 24th percentileScored 2026-11-07
Fix Fixed open-webui (open-webui): 0.11.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
open-webuiopen-webui0.11.1 to before 0.11.40.11.4Patch availableCNA
  • open-webui Vendoropen-webui Affected 0.11.1 to before 0.11.4 Fixed in 0.11.4 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*——open-webui
  • cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:* Versions — — ·open-webui

Remediation

Upgrade Open WebUI to version 0.11.4, which fixes this flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA open-webui (open-webui) Fixed in 0.11.4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    open-webui 0.11.4

    19 records Highest priority Priority HIGH 3 HIGH, 8 MEDIUM, 8 LOW

    Other records, highest priority first

    • TI-2026-71108 Session cookie disclosure in Open WebUI OAuth-mode connectionsPriority HIGH 68
    • TI-2026-71104 Stored cross-site scripting in Open WebUI markdown linksPriority HIGH 67
    • TI-2026-71114 Memory exhaustion in Open WebUI knowledge search via regex patternsPriority MEDIUM 64
    Show all 19 records →

Timeline

  1. 2026-10-12 Threatist record created from CVE-2026-109290
  2. 2026-10-12 Alias added: GHSA-39h3-jjqw-8pch
  3. 2026-10-13 Priority changed: MEDIUM → LOW
  4. 2026-10-13 CISA SSVC decision points changed
  5. 2026-10-13 Priority changed: LOW → HIGH
  6. 2026-10-24 CVSS score changed · CNA
  7. 2026-10-24 Weakness changed · CNA

References

Advisory 1

  • TI-2024-06216 Open WebUI Arbitrary File Upload + Path Traversal CVSS 3.1HIGH 8.8
  • TI-2024-07467 Improper Authentication in open-webui/open-webui CVSS 3.1HIGH 8.2
  • TI-2026-42359 Open WebUI: Cross-user code-interpreter and tool execution via unvalidated Socket.IO event-caller session_id CVSS 3.1CRITICAL 9.0
  • TI-2026-40759 open-webui - Remote Code Execution via CORS Misconfiguration and Session Validation CVSS 4.0CRITICAL 9.0
  • TI-2024-07431 Cross-site Scripting (XSS) in open-webui/open-webui CVSS 3.0CRITICAL 9.0
  • TI-2026-60021 Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin CVSS 3.1HIGH 8.7
See all 175 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences