CVE-2026-45387Public exploitNetwork attack vector

Authenticated system-prompt disclosure via model-detail endpoint

Published May 15, 2026 · Updated May 15, 2026

Information disclosure in Open WebUI before 0.9.5 allows remote authenticated users with model read access to retrieve its system prompt. The /api/v1/models/model endpoint returns params.system for a supplied model identifier even when that model is absent from the caller's editable-model list. Group-level read permission and knowledge of the model identifier are required; saving changes is blocked, so the demonstrated impact is limited to prompt confidentiality.

CVSS severity4.3
Medium
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

Information disclosure in Open WebUI before 0.9.5 allows remote authenticated users with model read access to retrieve its system prompt. The /api/v1/models/model endpoint returns params.system for a supplied model identifier even when that model is absent from the caller's editable-model list. Group-level read permission and knowledge of the model identifier are required; saving changes is blocked, so the demonstrated impact is limited to prompt confidentiality.

The record

CVE
CVE-2026-45387
Published
May 15, 2026
Updated
May 15, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-200, T1213
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 15, 2026CVE publishedPublication date reported by the CVE source.
  2. May 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=< 0.9.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=< 0.9.5

Published CVSS scores

4.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1213Data from Information Repositories

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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