CVE-2026-27769

Mattermost versions 10.11.x <= 10.11.12 fail to validate whether users were correctly owned by the correct Connected Workspace which allows a malicious remote server connected using the Conntexted Workspaces feature to change the displayed status of local users via the Connected Workspaces API.. Mattermost Advisory ID: MMSA-2026-00603

CVSS v3 2.7 LOW

2.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://mattermost.com/security-updates	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-15 11:16

Updated : 2026-06-17 10:27

NVD link : CVE-2026-27769

Mitre link : CVE-2026-27769

CVE.ORG link : CVE-2026-27769

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-862

Missing Authorization

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