{"id":"CVE-2024-39274","aliases":["GHSA-cmc8-222c-vqp9","GO-2024-3028"],"url":"https://o3.security/vulnerability/CVE-2024-39274","summary":"Malicious remote can add users to arbitrary teams and channels","details":"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 properly validate that the channel that comes from the sync message is a shared channel, when shared channels are enabled, which allows a malicious remote to add users to arbitrary teams and channels","published":"2024-08-01T14:05:02.518Z","modified":"2026-08-12T03:51:29.441256375Z","cvss":{"score":8.7,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"9.5.7"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"9.7.6"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"9.8.2"},{"ecosystem":"Go","name":"github.com/mattermost/mattermost/server/v8","fixedVersion":"9.9.1"}],"fix":null,"references":[{"type":"WEB","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/39xxx/CVE-2024-39274.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-39274"},{"type":"PACKAGE","url":"https://github.com/mattermost/mattermost"},{"type":"WEB","url":"https://pkg.go.dev/vuln/GO-2024-3028"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:29.441256375Z"}}