CVE-2026-75588 — Mattermost Desktop App plugin popout scheme validation bypass
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-posi…
Published: 2026-09-17 · CVSS: 2.6 · CVSS 3.1
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
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7