Security advisory

{
  "id": "88e354ea44a3db8621af6a3bd96ebb3d683902f8436f38a3c051317658006b4d",
  "url": "https://osv.dev/vulnerability/CVE-2017-18897",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2017-18897",
    "summary": "An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. It mishandles a deny action for a redirection.",
    "evidence": "osv:CVE-2017-18897",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2017-18897",
      "aliases": [
        "CVE-2017-18897",
        "GHSA-f7c3-7vp3-44p6",
        "GO-2026-4301"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mattermost/mattermost",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "ff513427371cd84e07b19c0586d419dbed976b31"
                },
                {
                  "introduced": "0033e3e37b12cb5d951d21492500d66a6abc472b"
                },
                {
                  "fixed": "5549c9149e80537d0f431b6b3ebf638c35568c4f"
                },
                {
                  "introduced": "f968c56890bd84295672ee0d46cc846cac2dbd47"
                },
                {
                  "last_affected": "a5ce36d0882ae1b4b409a7b68233bf89591a5f95"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.0.5"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.1.0"
                      },
                      {
                        "fixed": "4.1.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.2.0:rc1:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.2.0-rc1"
                      },
                      {
                        "last_affected": "4.2.0-rc1"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.2.0:rc2:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.2.0-rc2"
                      },
                      {
                        "last_affected": "4.2.0-rc2"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.2.0:rc3:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.2.0-rc3"
                      },
                      {
                        "last_affected": "4.2.0-rc3"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "cpe": "cpe:2.3:a:mattermost:mattermost_server:4.2.0:rc4:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.2.0-rc4"
                      },
                      {
                        "last_affected": "4.2.0-rc4"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "4.2.0-rc1",
            "4.2.0-rc2",
            "4.2.0-rc3",
            "4.2.0-rc4",
            "v4.2.0-rc4",
            "v4.2.0",
            "v4.2.0-rc3",
            "v4.2.0-rc2",
            "v4.2.0-rc1",
            "v4.0.4-rc1",
            "v4.0.4",
            "v4.1.0",
            "v4.0.3",
            "v4.0.2",
            "v4.0.1",
            "v4.0.0",
            "v0.5.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2017-18897.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:39.611533204Z",
      "provider": "osv",
      "references": [
        "https://mattermost.com/security-updates/"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2017-18897",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 434710,
  "published_at": "2020-06-19T19:15:11.327+00:00"
}