CVE-2026-45386Public exploitNetwork attack vector

Authenticated message pinning via read-only permission check

Published May 15, 2026 · Updated May 15, 2026

Authorization bypass in Open WebUI before 0.9.5 allows remote authenticated users to pin or unpin standard-channel messages. The pin_channel_message endpoint treats this write operation as authorized when channel_has_access confirms only read permission, then changes the message's is_pinned, pinned_by, and pinned_at fields. A read-only standard-channel grant is sufficient, and the demonstrated consequence is disruption of which messages appear pinned, without reported confidentiality or availability impact.

CVSS severity4.3
Medium
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Open WebUI before 0.9.5 allows remote authenticated users to pin or unpin standard-channel messages. The pin_channel_message endpoint treats this write operation as authorized when channel_has_access confirms only read permission, then changes the message's is_pinned, pinned_by, and pinned_at fields. A read-only standard-channel grant is sufficient, and the demonstrated consequence is disruption of which messages appear pinned, without reported confidentiality or availability impact.

The record

CVE
CVE-2026-45386
Published
May 15, 2026
Updated
May 15, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-639, T1565.001
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:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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-639Authorization Bypass Through User-Controlled Key
T1565.001Stored Data Manipulation

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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