CVE-2026-54006Public exploitNetwork attack vector

Cross-user calendar writes via unchecked re-parenting

Published Jun 23, 2026 · Updated Jun 23, 2026

Authorization bypass in Open WebUI before 0.9.6 allows remote authenticated users to write events into another user's calendar. The event update endpoint checks write access only to the event's current calendar, while update_event_by_id persists a caller-supplied destination calendar_id without an access check. A regular user-role account can exploit the default-enabled calendar feature after learning a target calendar ID, inserting arbitrary event content but gaining no read access or continued control after the move.

CVSS severity4.3
Medium
EPSS probability0.30%
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 0.9.6 allows remote authenticated users to write events into another user's calendar. The event update endpoint checks write access only to the event's current calendar, while update_event_by_id persists a caller-supplied destination calendar_id without an access check. A regular user-role account can exploit the default-enabled calendar feature after learning a target calendar ID, inserting arbitrary event content but gaining no read access or continued control after the move.

The record

CVE
CVE-2026-54006
Published
Jun 23, 2026
Updated
Jun 23, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-639, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 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=< 0.9.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=< 0.9.6

Published CVSS scores

4.3Open WebUICVSS: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

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-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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