GHSA-qwwm-c582-82rx Mattermost allows unauthorized channel member management through playbook runs

• Go github.com/mattermost/mattermost-server: < 0.0.0-20250520060012-d0380305ef7a → fixed in 0.0.0-20250520060012-d0380305ef7a • Go github.com/mattermost/mattermost/server/v8: < 8.0.0-20250520060012-d0380305ef7a → fixed in 8.0.0-20250520060012-d0380305ef7a • Go github.com/mattermost/mattermost/server/v8: >= 10.5.0, < 10.5.6 → fixed in 10.5.6 • Go github.com/mattermost/mattermost/server/v8: >= 9.11.0, < 9.11.16 → fixed in 9.11.16 • Go github.com/mattermost/mattermost/server/v8: >= 10.8.0, < 10.8.1 → fixed in 10.8.1 • Go github.com/mattermost/mattermost/server/v8: >= 10.7.0, < 10.7.3 → fixed in 10.7.3 • Go github.com/mattermost/mattermost/server/v8: >= 10.6.0, < 10.6.6 → fixed in 10.6.6

Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions in playbook runs, allowing authenticated users without the 'Manage Channel Members' permission to add or remove users from public and private channels by manipulating playbook run participants when the run is linked to a channel.