Security advisory

{
  "id": "2be2e0ece73a466c5273f0e15cab57e5d135b2a541d6b07e8d9e626874166d78",
  "url": "https://osv.dev/vulnerability/CVE-2019-20887",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2019-20887",
    "summary": "An issue was discovered in Mattermost Server before 5.7.1, 5.6.4, 5.5.3, and 4.10.6. It does not honor flags API permissions when deciding whether a user can receive intra-team posts.",
    "evidence": "osv:CVE-2019-20887",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2019-20887",
      "aliases": [
        "CVE-2019-20887"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mattermost/mattermost",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "f864d327b53e7d23ee7362fb94f6c857971e2875"
                },
                {
                  "introduced": "826252252404c13bf564a8c4fd51616fc2cc4df9"
                },
                {
                  "fixed": "8e0e9672269b4fddbf9e1329eb44e654e40edb1e"
                },
                {
                  "introduced": "0c1207215852a8726c3f09dea157d597fec368df"
                },
                {
                  "fixed": "4dcd132c1494f53cf6a2ab5cb24a3425a4bc1089"
                },
                {
                  "introduced": "7e5fda43bda67cd061e527b64046f241c2d6cc32"
                },
                {
                  "fixed": "ad3ddac9b935fb842ca4301f69266ffb87ec8c86"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.10.6"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "5.5.0"
                      },
                      {
                        "fixed": "5.5.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "5.6.0"
                      },
                      {
                        "fixed": "5.6.4"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "5.7.0"
                      },
                      {
                        "fixed": "5.7.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v5.5.2-rc1",
            "v5.5.2",
            "v5.6.3-rc1",
            "v5.6.3",
            "v5.7.0-rc6",
            "v5.7.0",
            "v4.10.5-rc1",
            "v4.10.5",
            "v4.10.4-rc1",
            "v4.10.4",
            "v5.6.2-rc1",
            "v5.6.2",
            "v5.6.1-rc3",
            "v5.6.1-rc2",
            "v5.6.1-rc1",
            "v5.6.1",
            "v5.6.0-rc6",
            "v5.6.0",
            "v5.5.1-rc1",
            "v5.5.1",
            "v5.5.0-rc3",
            "v5.5.0",
            "v4.10.3-rc1",
            "v4.10.3",
            "v4.10.2-rc1",
            "v4.10.2",
            "v4.10.1-rc1",
            "v4.10.1",
            "v4.10.0-rc5",
            "v4.10.0-rc4",
            "v4.10.0",
            "v4.10.0-rc3",
            "v4.10.0-rc2",
            "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-2019-20887.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:37.107344989Z",
      "provider": "osv",
      "references": [
        "https://mattermost.com/security-updates/"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2019-20887",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 434143,
  "published_at": "2020-06-19T17:15:13.897+00:00"
}