Mattermost versions 10.0.x <= 10.0.0 and 9.11.x <= 9.11.2 fail to properly query ElasticSearch when searching for the channel name in channel switcher which allows an attacker to get private channels names of channels that they are not a member of, when Elasticsearch v8 was enabled.
{
"cpes": [
"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
"cpe:2.3:a:mattermost:mattermost_server:10.0.0:-:*:*:*:*:*:*",
"cpe:2.3:a:mattermost:mattermost_server:10.0.0:rc1:*:*:*:*:*:*",
"cpe:2.3:a:mattermost:mattermost_server:10.0.0:rc2:*:*:*:*:*:*",
"cpe:2.3:a:mattermost:mattermost_server:10.0.0:rc3:*:*:*:*:*:*",
"cpe:2.3:a:mattermost:mattermost_server:10.0.0:rc4:*:*:*:*:*:*"
],
"severity": "Medium"
}