CVE-2026-75588: mattermost desktop from 6.2.0 (inclusive), before 6.2.3 (exclusive); +1 more affected products

Affected technology

mattermost desktop · from 6.2.0 (inclusive), before 6.2.3 (exclusive)
mattermost

Mattermost · 0 through 6.2.2
Mattermost

Description’s affected range: 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

Component: Not specified by the source

Attack conditions (Vendor/CNA, CVSS 3.1): Network (remote) · Low privileges required · User interaction required

What an attacker can do

The source says 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. Vendor/CNA’s CVSS 3.1 assessment (base score 2.6/10) rates confidentiality and availability impact as none; integrity impact as low.