CVE-2026-75588

Mattermost Desktop App versions <=6.2 6.2.2.0 fail to validate the URL scheme when checking whether a target URL is internal to the connected server, which allows a network-positioned attacker to load a plugin popout window over an insecure connection via a link using a downgraded URL scheme. Mattermost Advisory ID: MMSA-2026-00717

CVSS v3 2.6 LOW

2.6^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*

History

13 Oct 2026, 12:02

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

17 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 16:17

Updated : 2026-10-13 12:02

NVD link : CVE-2026-75588

Mitre link : CVE-2026-75588

CVE.ORG link : CVE-2026-75588

JSON object : View

Products Affected

mattermost

mattermost_desktop

CWE

CWE-1287

Improper Validation of Specified Type of Input

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