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CVE-2026-14344— Inconsistent authorization checks in Mattermost Boards endpoints

Quick assessment

Affected
Mattermost Mattermost
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Mattermost是美国Mattermost公司开源的一个开源协作平台。 Mattermost 11.9.0及之前的11.9.x版本、11.8.4及之前的11.8.x版本、11.7.7及之前的11.7.x版本和10.11.22及之前的10.11.x版本存在授权问题漏洞,该漏洞源于未强制实施board-creation权限,导致未经授权的已认证用户可通过board duplicate、boards-and-blocks和archive-import端点创建看板。

CVSS 4.3 · Medium EPSS 0.25% · P17

Affected Version Matrix 9

VendorProduct Version RangeStatus
Mattermost Mattermost 11.9.0≤ 11.9.0 affected
11.8.0≤ 11.8.4 affected
11.7.0≤ 11.7.7 affected
10.11.0≤ 10.11.22 affected
11.10.0 unaffected
11.9.1 unaffected
11.8.5 unaffected
11.7.8 unaffected
… +1 more rows
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I. Basic Information for CVE-2026-14344

Vulnerability Information

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Vulnerability Title
Inconsistent authorization checks in Mattermost Boards endpoints
Source: CVE Program / CVE List V5
Vulnerability Description
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to enforce the board-creation permission which allows an unauthorized authenticated user to create boards via the board duplicate, boards-and-blocks, and archive-import endpoints.. Mattermost Advisory ID: MMSA-2026-00715
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
授权机制缺失
Source: CVE Program / CVE List V5
Vulnerability Title
Mattermost 授权问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Mattermost是美国Mattermost公司开源的一个开源协作平台。 Mattermost 11.9.0及之前的11.9.x版本、11.8.4及之前的11.8.x版本、11.7.7及之前的11.7.x版本和10.11.22及之前的10.11.x版本存在授权问题漏洞,该漏洞源于未强制实施board-creation权限,导致未经授权的已认证用户可通过board duplicate、boards-and-blocks和archive-import端点创建看板。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Mattermost Mattermost 11.9.0 ~ 11.9.0 -

II. Public POCs for CVE-2026-14344

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III. Intelligence Information for CVE-2026-14344

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Same Patch Batch · Mattermost · 2026-09-14 · 16 CVEs total

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CVE-2026-5132 6.5 MEDIUM Unbounded zlib decompression in Calls SDP WebSocket messages
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CVE-2026-82920 5.5 MEDIUM Mattermost ABAC parent policy bypass via policy update endpoint
CVE-2026-10556 5.3 MEDIUM Unauthenticated webhook request with null notification entry could crash the Microsoft Cal
CVE-2026-10542 5.0 MEDIUM Playbooks channel action update validation issue
CVE-2026-11993 4.3 MEDIUM Fix authenticated members disabling file content indexing server-wide via extraction pool
CVE-2026-14259 4.3 MEDIUM Board archive import bypasses team board creation permissions
CVE-2026-12882 4.3 MEDIUM Mattermost Markdown autolink parsing denial of service
CVE-2026-13417 4.3 MEDIUM Boards plugin denial of service via unvalidated block fields.properties
CVE-2026-86348 4.3 MEDIUM MS Calendar plugin: unrecovered handler panics from malformed post-action requests could c
CVE-2026-86349 4.3 MEDIUM Mattermost Server Algorithmic DoS via Unbounded Markdown Block Nesting

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