CVE-2026-14344Network attack vectorHinoki check available

Unauthorized board creation via omitted permission checks

Published Sep 14, 2026 · Updated Sep 14, 2026

Authorization bypass in Mattermost allows remote authenticated users lacking board-creation permission to create boards through three API paths. The Boards handlers for duplication, boards-and-blocks creation, and archive import did not consistently enforce team public or private creation permissions before persisting a board. Any authenticated account able to reach these endpoints can add unauthorized boards to a team and change workspace data without the assigned creation permission.

CVSS severityUnavailable
Unscored
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Authorization bypass in Mattermost allows remote authenticated users lacking board-creation permission to create boards through three API paths. The Boards handlers for duplication, boards-and-blocks creation, and archive import did not consistently enforce team public or private creation permissions before persisting a board. Any authenticated account able to reach these endpoints can add unauthorized boards to a team and change workspace data without the assigned creation permission.

The record

CVE
CVE-2026-14344
Published
Sep 14, 2026
Updated
Sep 14, 2026
Vendor
Mattermost
Product
Mattermost
Classifications
Unavailable
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 14, 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=10.11.0 <=10.11.22
  2. Affected versionversion=11.7.0 <=11.7.7
  3. Affected versionversion=11.8.0 <=11.8.4
  4. Affected versionversion=11.9.0 <=11.9.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=10.11.0 <=10.11.22; version=11.7.0 <=11.7.7; version=11.8.0 <=11.8.4; version=11.9.0 <=11.9.0

Published CVSS scores

No CVSS assessment is available in this record.

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

No sourced classifications are available.

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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