CVE-2026-9820

Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671

CVSS v3 3.8 LOW

3.8^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::

History

13 Jul 2026, 20:38

Type	Values Removed	Values Added
First Time		Mattermost mattermost Server Mattermost
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
CPE		cpe:2.3:a:mattermost:mattermost_server::::::::

13 Jul 2026, 11:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-13 11:16

Updated : 2026-07-13 20:38

NVD link : CVE-2026-9820

Mitre link : CVE-2026-9820

CVE.ORG link : CVE-2026-9820

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-862

Missing Authorization

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