CVE-2026-87012Network attack vector

Calendar-alert suppression via unvalidated alert offset

Published Sep 9, 2026 · Updated Sep 9, 2026

Improper input validation in Open WebUI 0.9.0 through 0.11.0 allows remote authenticated users to suppress calendar alerts. Calendar events store meta.alert_minutes without type validation, and the shared scheduler numerically compares the value without per-event exception handling. Default calendar permission is sufficient; a nonnumeric value aborts the instance-wide pass, but chat, APIs, and data access remain unaffected.

CVSS severity4.3
Medium
EPSS probability0.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Open WebUI 0.9.0 through 0.11.0 allows remote authenticated users to suppress calendar alerts. Calendar events store meta.alert_minutes without type validation, and the shared scheduler numerically compares the value without per-event exception handling. Default calendar permission is sufficient; a nonnumeric value aborts the instance-wide pass, but chat, APIs, and data access remain unaffected.

The record

CVE
CVE-2026-87012
Published
Sep 9, 2026
Updated
Sep 9, 2026
Vendor
Open WebUI
Product
Open WebUI
Classifications
CWE-1287, CWE-754, T1499.004
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

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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=>= 0.9.0, < 0.11.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Open WebUI · Open WebUIversion=>= 0.9.0, < 0.11.1

Published CVSS scores

4.3GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-1287Improper Validation of Specified Type of Input
CWE-754Improper Check for Unusual or Exceptional Conditions
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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