Mattermost doesn't validate file ownership and access control
Go github.com/mattermost/mattermost-server · Upgrade to 11.6.1, 11.5.4, 11.4.5 or 10.11.15 by release line · >= 11.6.0, <= 11.6.0; >= 11.5.0, < 11.5.4; >= 11.4.0, < 11.4.5; >= 10.11.0, < 10.11.15 · CVE-2026-3473 · GHSA-7pf2-9c95-w332