CVE-2026-3108

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to sanitize user-controlled post content in the mmctl commands terminal output which allows attackers to manipulate administrator terminals via crafted messages containing ANSI and OSC escape sequences that enable screen manipulation, fake prompts, and clipboard hijacking.. Mattermost Advisory ID: MMSA-2026-00599

CVSS v3 8.0 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

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::::::::
	cpe:2.3:a:mattermost:mattermost_server::::::::
	cpe:2.3:a:mattermost:mattermost_server:11.4.0:::::::*

History

30 Mar 2026, 19:45

Type	Values Removed	Values Added
References	~~() https://mattermost.com/security-updates -~~	() https://mattermost.com/security-updates - Vendor Advisory
First Time		Mattermost mattermost Server Mattermost
CPE		cpe:2.3:a:mattermost:mattermost_server:::::::: cpe:2.3:a:mattermost:mattermost_server:11.4.0:::::::*

Information

Published : 2026-03-26 17:16

Updated : 2026-03-30 19:45

NVD link : CVE-2026-3108

Mitre link : CVE-2026-3108

CVE.ORG link : CVE-2026-3108

JSON object : View

Products Affected

mattermost

mattermost_server

CWE

CWE-150

Improper Neutralization of Escape, Meta, or Control Sequences

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