CVE-2026-87995

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

Published: Sep 9, 2026Updated: Sep 16, 2026 Sources: CVE List NVDCWE-79

8.7HIGH

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:RUser Interaction

Required

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-79 CWE-1021

Affected Products

open-webui

oss-projectaka open-webui/open-webui

open-webuiOn-premWeb App

AI / ML / ai-agent-tooling

openwebui

oss-projectaka open webui

open webuiOn-premWeb App

AI / ML / ai-agent-tooling

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Execution

Initial Access

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References

https://github.com/open-webui/open-webui/security/advisories/GHSA-jmc6-2wr8-h3wj

github.com

https://github.com/open-webui/open-webui/commit/54d7a223707f03172efbb9e754db6e69709956d0

github.com

https://github.com/open-webui/open-webui/releases/tag/v0.11.1

github.com

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