Malicious remote can create arbitrary channels

{
  "id": "d7882e5fe9eccc31102440b44813fe12c373bfb5583e9145257522ee73a5826b",
  "url": "https://osv.dev/vulnerability/CVE-2024-39837",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Malicious remote can create arbitrary channels",
    "summary": "Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly restrict channel creation which allows a malicious remote to create arbitrary channels, when shared channels were enabled.",
    "evidence": "osv:CVE-2024-39837",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2024-39837",
      "aliases": [
        "BIT-mattermost-2024-39837",
        "CVE-2024-39837",
        "GHSA-vvpg-55p7-5h8w",
        "GO-2024-3032"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mattermost/mattermost",
              "type": "GIT",
              "events": [
                {
                  "introduced": "99d819d25d0b16b3faed901b1fe5c41de7655e9c"
                },
                {
                  "fixed": "55b24d27c857936c742992b6e3ca94bb2c5c3dac"
                },
                {
                  "introduced": "4179e17b491ec5292ca6e157d7b216b464bce397"
                },
                {
                  "last_affected": "4179e17b491ec5292ca6e157d7b216b464bce397"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "9.5.0"
                      },
                      {
                        "fixed": "9.5.7"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:9.9.0:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "9.9.0"
                      },
                      {
                        "last_affected": "9.9.0"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "9.9.0",
            "v9.5.7-rc2",
            "v9.5.7-rc1",
            "v9.5.6",
            "v9.9.0-rc4",
            "v9.9.0",
            "@mattermost/types@9.9.0",
            "@mattermost/client@9.9.0",
            "v9.5.6-rc2",
            "v9.5.6-rc1",
            "v9.5.5-rc1",
            "v9.5.5",
            "v9.5.4-rc2",
            "v9.5.4",
            "v9.5.4-rc1",
            "v9.5.3",
            "v9.5.3-rc3",
            "v9.5.3-rc2",
            "v9.5.3-rc1",
            "v9.5.2",
            "v9.5.1-rc1",
            "v9.5.1",
            "v9.5.0-rc3",
            "v9.5.0",
            "@mattermost/types@9.5.0",
            "@mattermost/client@9.5.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-39837.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.294353599Z",
      "provider": "osv",
      "references": [
        "https://mattermost.com/security-updates",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/39xxx/CVE-2024-39837.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2024-39837"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-284"
        ],
        "cna_assigner": "Mattermost",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "9.9.0"
                  },
                  {
                    "last_affected": "9.9.0"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandaloneSingleVersion"
              }
            ]
          },
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "9.5.0"
                  },
                  {
                    "last_affected": "9.5.6"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/39xxx/CVE-2024-39837.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2024-39837",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520011,
  "published_at": "2024-08-01T14:05:06.182+00:00"
}