CVE-2026-6345
Published:May 18, 2026
Updated:June 11, 2026
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail prevent disclosure of created user password which allows a malicious attacker to impersonate a user via the use of some of those passwords.. Mattermost Advisory ID: MMSA-2026-00614
Affected Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.4.0 <v11.4.4Fix Suggestion:
Update to version v11.4.4https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v10.11.0 <v10.11.14Fix Suggestion:
Update to version v10.11.14https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.5.0 <v11.5.2Fix Suggestion:
Update to version v11.5.2github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.5.0 <v11.5.2Fix Suggestion:
Update to version v11.5.2github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.4.0 <v11.4.4Fix Suggestion:
Update to version v11.4.4github.com/mattermost/mattermost/server/v8 (GO):
Affected version(s) >=v8.0.0-20230429093631-aac4f2337933 <v8.0.0-20260311102650-3057ae7e83e9Fix Suggestion:
Update to version v8.0.0-20260311102650-3057ae7e83e9github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.14Fix Suggestion:
Update to version v10.11.14Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.5
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Insufficiently Protected Credentials
EPSS
Base Score:
0.04