CVE-2026-87995Public exploitNetwork attack vector

Authenticated account takeover via same-origin terminal preview

Published Sep 9, 2026 · Updated Sep 9, 2026

Cross-site scripting in Open WebUI 0.8.11 through 0.11.0 allows remote authenticated users to take over accounts via a terminal port preview. The PortPreview.svelte component hardcodes allow-scripts with allow-same-origin on an iframe whose proxied content shares the application origin, letting hosted script read the victim's localStorage session token. Exploitation requires a configured shared terminal, a normal account able to host a listening process, default CSP-related settings, and a victim who opens the malicious port preview.

CVSS severity8.7
High
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Open WebUI 0.8.11 through 0.11.0 allows remote authenticated users to take over accounts via a terminal port preview. The PortPreview.svelte component hardcodes allow-scripts with allow-same-origin on an iframe whose proxied content shares the application origin, letting hosted script read the victim's localStorage session token. Exploitation requires a configured shared terminal, a normal account able to host a listening process, default CSP-related settings, and a victim who opens the malicious port preview.

The record

CVE
CVE-2026-87995
Published
Sep 9, 2026
Updated
Sep 9, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-79, CWE-1021, T1528
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 0.8.11, < 0.11.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=>= 0.8.11, < 0.11.1

Published CVSS scores

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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-1021Improper Restriction of Rendered UI Layers or Frames
T1528Steal Application Access Token

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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