Vulnerability DatabaseCVE-2026-18795
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CVE-2026-18795
Published:October 16, 2026
Updated:October 20, 2026
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to enforce DM/GM check on server side which allows an authenticated user to quarantine a post belonging to DM or GM via direct API call.. Mattermost Advisory ID: MMSA-2026-00756
Affected Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) =v11.10.0 <v11.10.1
Fix Suggestion:
Update to version v11.10.1
Related Resources (2)
https://mattermost.com/security-updates
https://nvd.nist.gov/vuln/detail/CVE-2026-18795
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CVSS v4
Base Score:
6.1
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
LOW
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.4
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
LOW
Availability
LOW
Weakness Type (CWE)
Missing Authorization
CWE-862
EPSS
Base Score:
0.15