Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin (CVE-2026-87995) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-87995

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

Answer in brief

CVE-2026-87995 records a Unknown severity vulnerability in Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin. The current sources do not mark it as known exploited. The current feed maps open-webui/open-webui (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 9, 2026Updated Sep 9, 2026Source checked Sep 9, 2026First seen by HOL Sep 9, 2026Material review Sep 9, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps open-webui/open-webui (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
open-webui/open-webuigeneric	>= 0.8.11, < 0.11.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for open-webui/open-webui.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 9, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 9, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.