CVE-2026-87995CWE-1021CWE-79cross-site-scripting

CVE-2026-87995

High · published September 10, 2026

CVSS v3.1
8.7
EPSS
0%
Percentile
34.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.7 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00417 · 34.9th percentile
Weaknesses
CWE-1021 · Improper Restriction of Rendered UI Layers or Frames; CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-09-10T02:18Z
Affected products (1)
ProductVersionsFixed in
openwebui/open_webui≥ 0.8.11, < 0.11.10.11.1
References (4)
https://github.com/open-webui/open-webui/commit/54d7a223707f03172efbb9e754db6e69709956d0 · [email protected]https://github.com/open-webui/open-webui/releases/tag/v0.11.1 · [email protected]https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj · [email protected]https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 11 SEP 03:19Z
    EPSS moved — → 0%
    epss
  • 09 SEP 21:26Z
    Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin
    cvelistv5