{"id":"CVE-2024-39274","aliases":["EUVD-2024-2562","GHSA-cmc8-222c-vqp9","GO-2024-3028"],"status":"published","title":"Malicious remote can add users to arbitrary teams and channels","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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 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Advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2024-39274","tags":["advisory"]},{"url":"https://pkg.go.dev/vuln/GO-2024-3028","tags":["web"]},{"url":"https://github.com/advisories/GHSA-cmc8-222c-vqp9","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/39xxx/CVE-2024-39274.json","tags":["advisory"]},{"url":"https://github.com/mattermost/mattermost","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2024-39274","title":"Malicious remote can add users to arbitrary teams and channels","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T14:05:02.518Z","modified":"2024-08-02T15:10:58.701Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:34:18.951288Z"}],"euvd":[{"id":"EUVD-2024-2562","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T14:05:02Z","modified":"2024-08-02T15:10:58Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:50:05.016714Z"}],"ghsa":[{"id":"GHSA-cmc8-222c-vqp9","title":"Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T15:32:21Z","modified":"2024-11-18T16:26:59Z","cvss":[{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N","level":"critical"},{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:38:20.012356Z"}],"nvd":[{"id":"CVE-2024-39274","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T15:15:12.15Z","modified":"2026-06-17T07:41:36.727Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T14:10:15.933769Z"}],"osv":[{"id":"CVE-2024-39274","title":"Malicious remote can add users to arbitrary teams and channels","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T14:05:02.518Z","modified":"2026-10-28T02:30:49.853701104Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T15:44:41.618074Z"},{"id":"GHSA-cmc8-222c-vqp9","title":"Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel","description":"Mattermost versions 9.9.x \u003c= 9.9.0, 9.5.x \u003c= 9.5.6, 9.7.x \u003c= 9.7.5 and 9.8.x \u003c= 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","status":"published","published":"2024-08-01T15:32:21Z","modified":"2024-11-18T16:26:58Z","cvss":[{"version":"3.1","score":8.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","level":"high"},{"version":"4.0","score":9.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N","level":"critical"}],"cwes":["CWE-284"],"updated_at":"2026-11-02T15:46:45.28161Z"},{"id":"GO-2024-3028","title":"Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel in github.com/mattermost/mattermost-server","description":"Mattermost failed to properly validate that the channel that comes from the sync message is a shared channel in github.com/mattermost/mattermost-server","status":"published","published":"2024-08-06T22:03:16Z","modified":"2026-03-03T04:55:37.237876Z","updated_at":"2026-11-02T15:47:01.453823Z"}]}}