Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to disallow unsolicited invites to expose access to local channels, when shared channels are enabled, which allows a malicious remote to send an invite with the ID of an existing local channel, and that local channel will then become shared without the consent of the local admin.
{
"nvd_published_at": "2024-08-01T15:15:12Z",
"severity": "CRITICAL",
"github_reviewed_at": "2024-08-23T18:51:05Z",
"github_reviewed": true,
"cwe_ids": [
"CWE-284"
]
}