{"id":"CVE-2018-21251","details":"An issue was discovered in Mattermost Server before 5.2 and 5.1.1. Authorization could be bypassed if the channel name were not the same in the params and the body.","modified":"2026-08-27T08:14:33.100957Z","published":"2020-06-19T17:15:12.490Z","references":[{"type":"ADVISORY","url":"https://mattermost.com/security-updates/"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/mattermost/mattermost","events":[{"introduced":"0"},{"fixed":"77274a7aca64491a1898d4e4239158817a503a8e"},{"introduced":"9bf01f1401ed47afc4fc443974e2bd4db50b2f50"},{"last_affected":"43483805eabcb36ef9018f12a82a6d3ac055baf5"}],"database_specific":{"cpe":["cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc1:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc2:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc3:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc4:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc5:*:*:*:*:*:*","cpe:2.3:a:mattermost:mattermost_server:5.2.0:rc6:*:*:*:*:*:*"],"extracted_events":[{"introduced":"0"},{"fixed":"5.1.1"},{"introduced":"5.2.0-rc1"},{"last_affected":"5.2.0-rc1"},{"introduced":"5.2.0-rc2"},{"last_affected":"5.2.0-rc2"},{"introduced":"5.2.0-rc3"},{"last_affected":"5.2.0-rc3"},{"introduced":"5.2.0-rc4"},{"last_affected":"5.2.0-rc4"},{"introduced":"5.2.0-rc5"},{"last_affected":"5.2.0-rc5"},{"introduced":"5.2.0-rc6"},{"last_affected":"5.2.0-rc6"}],"source":["CPE_RANGE","CPE_STRING"]}}],"versions":["5.2.0-rc1","5.2.0-rc3","5.2.0-rc5","v5.2.0-rc6","v5.2.0-rc5","v5.2.0","v5.2.0-rc4","v5.2.0-rc3","v5.2.0-rc2","v5.2.0-rc1","v5.1.0-rc4","v5.1.0","v5.1.0-rc3","v5.1.0-rc2","v5.1.0-rc1","v5.0.0-rc1","v4.10.0-rc1","v4.9.0-rc1","v4.8.0-rc1","v4.7.0-rc1","v4.6.0-rc2","v4.6.0-rc1","v4.5.0-rc1","v4.4.0-rc1","v4.3.0-rc1","v4.2.0-rc1","v0.5.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-21251.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}