Security advisory

{
  "id": "482ae14c621f16fae4ebfd749e24d91f91e66b4cdeaa05d53b2eeac6c8be3398",
  "url": "https://osv.dev/vulnerability/CVE-2018-21263",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-21263",
    "summary": "An issue was discovered in Mattermost Server before 4.7.0, 4.6.2, and 4.5.2. An attacker could authenticate to a different user's account via a crafted SAML response.",
    "evidence": "osv:CVE-2018-21263",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2018-21263",
      "aliases": [
        "CVE-2018-21263"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mattermost/mattermost",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "03f5c939deb4a6ab2fd01639b5570799e4118bab"
                },
                {
                  "introduced": "58defb7424773c75718f0173f4ace702cffa4f0e"
                },
                {
                  "fixed": "cc82749d4f8c47bce201123aedcd8c564ceffcb8"
                },
                {
                  "introduced": "9a73f9988588b6b1be5711634239381fe9e01d16"
                },
                {
                  "last_affected": "9360131992064203f9ee46fa0504d20276c97339"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.5.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.6.0"
                      },
                      {
                        "fixed": "4.6.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.7.0:rc1:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.7.0-rc1"
                      },
                      {
                        "last_affected": "4.7.0-rc1"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.7.0:rc2:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.7.0-rc2"
                      },
                      {
                        "last_affected": "4.7.0-rc2"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.7.0:rc3:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.7.0-rc3"
                      },
                      {
                        "last_affected": "4.7.0-rc3"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.7.0:rc4:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.7.0-rc4"
                      },
                      {
                        "last_affected": "4.7.0-rc4"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "4.7.0-rc1",
            "4.7.0-rc2",
            "4.7.0-rc3",
            "4.7.0-rc4",
            "v4.7.0-rc4",
            "v4.7.0",
            "v4.7.0-rc3",
            "v4.7.0-rc2",
            "v4.7.0-rc1",
            "v4.6.0-rc6",
            "v4.6.0-rc5",
            "v4.6.0",
            "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-2018-21263.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:45.336190536Z",
      "provider": "osv",
      "references": [
        "https://mattermost.com/security-updates/"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2018-21263",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 436108,
  "published_at": "2020-06-19T17:15:13.067+00:00"
}