CVE-2026-87995 PUBLISHED

Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin

Assigner: GitHub_M
Reserved: 09.09.2026 Published: 09.09.2026 Updated: 09.09.2026

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.8.11 until 0.11.1, src/lib/components/chat/FileNav/PortPreview.svelte rendered terminal port content in an iframe sandbox containing both allow-scripts and allow-same-origin. Because the terminal proxy serves that content from the Open WebUI origin, an authenticated user with access to a shared terminal server could host script on a previewed port and take over a victim's account when the victim opened the preview. This issue is fixed in version 0.11.1.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
CVSS Score: 8.7

Product Status

Vendor open-webui
Product open-webui
Versions
  • Version >= 0.8.11, < 0.11.1 is affected

References

Problem Types

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE
  • CWE-1021: Improper Restriction of Rendered UI Layers or Frames CWE