{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "5.1.1"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc1"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc2"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc3"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc4"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc5"
              },
              {
                "introduced": "0"
              },
              {
                "last_affected": "5.2.0-rc6"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "77274a7aca64491a1898d4e4239158817a503a8e"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "9bf01f1401ed47afc4fc443974e2bd4db50b2f50"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "9bf01f1401ed47afc4fc443974e2bd4db50b2f50"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "687700a989810ec99bc6b52a1e3900a237a4cd54"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "687700a989810ec99bc6b52a1e3900a237a4cd54"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "43483805eabcb36ef9018f12a82a6d3ac055baf5"
            },
            {
              "introduced": "0"
            },
            {
              "last_affected": "43483805eabcb36ef9018f12a82a6d3ac055baf5"
            }
          ],
          "repo": "https://github.com/mattermost/mattermost-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "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.",
  "id": "CVE-2018-21251",
  "modified": "2026-03-13T21:48:23.266588608Z",
  "published": "2020-06-19T17:15:12.490Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://mattermost.com/security-updates/"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}