Vulnerability DatabaseCVE-2026-3636
Mend.io Vulnerability Database
The largest open source vulnerability database
What is a Vulnerability ID?
New vulnerability? Tell us about it!
CVE-2026-3636
Published:May 22, 2026
Updated:June 11, 2026
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to sanitize team member data when returned via API to users without elevated permissions which allows a user without permissions to get data about team members roles via invoking various team API endpoints.. Mattermost Advisory ID: MMSA-2026-00626
Affected Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.4.0 <v11.4.5
Fix Suggestion:
Update to version v11.4.5
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v10.11.0 <v10.11.15
Fix Suggestion:
Update to version v10.11.15
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) =v11.6.0 <v11.6.1
Fix Suggestion:
Update to version v11.6.1
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.5.0 <v11.5.4
Fix Suggestion:
Update to version v11.5.4
github.com/mattermost/mattermost (GO):
Affected version(s) =v11.6.0 <v11.6.1
Fix Suggestion:
Update to version v11.6.1
github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.15
Fix Suggestion:
Update to version v10.11.15
github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.4.0 <v11.4.5
Fix Suggestion:
Update to version v11.4.5
github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.5.0 <v11.5.4
Fix Suggestion:
Update to version v11.5.4
Related Resources (1)
https://mattermost.com/security-updates
Do you need more information?
Contact Us
CVSS v4
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Exposure of Sensitive Information to an Unauthorized Actor
CWE-200
EPSS
Base Score:
0.03