Security advisory

{
  "id": "c3d0981a2f0b3fbc4574143ea643da1937563c1a7c1b4db8a6f5a741102528c6",
  "url": "https://osv.dev/vulnerability/CVE-2018-3761",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-3761",
    "summary": "Nextcloud Server before 12.0.8 and 13.0.3 suffer from improper authentication on the OAuth2 token endpoint. Missing checks potentially allowed handing out new tokens in case the OAuth2 client was partly compromised.",
    "evidence": "osv:CVE-2018-3761",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2018-3761",
      "aliases": [
        "CVE-2018-3761"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/nextcloud/server",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "42d3169e276bda2e2c41849fcc8a6f683719b323"
                },
                {
                  "introduced": "3b4285e13f6b1ec074b98466f49e189101f090bc"
                },
                {
                  "fixed": "8a0093d9cada749aa0182b1c2248b42e0ea47f0b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "12.0.8"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "13.0.0"
                      },
                      {
                        "fixed": "13.0.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v13.0.3RC2",
            "v12.0.8RC1",
            "v13.0.3RC1",
            "theming-1.4.5",
            "v12.0.7",
            "v13.0.2",
            "v12.0.7RC1",
            "v13.0.2RC1",
            "v12.0.6",
            "v13.0.1",
            "v12.0.6RC1",
            "v13.0.1RC1",
            "v13.0.0",
            "v12.0.5",
            "v12.0.5RC3",
            "v12.0.5RC2",
            "v12.0.5RC1",
            "v12.0.4",
            "v12.0.4RC3",
            "v12.0.4RC2",
            "v12.0.4RC1",
            "v12.0.3",
            "v12.0.3RC2",
            "v12.0.3RC1",
            "v12.0.1",
            "v12.0.1RC5",
            "v12.0.1RC4",
            "v12.0.1RC3",
            "v12.0.1RC2",
            "v12.0.1RC1",
            "v12.0.0",
            "v12.0.0RC3",
            "v12.0.0RC2",
            "v12.0.0RC1",
            "v12.0.0beta4",
            "v12.0.0beta3",
            "v12.0.0beta2",
            "v12.0.0beta1",
            "v11.0.0",
            "v11.0RC2",
            "v9.1.0beta1",
            "v9.0.0beta2",
            "v9.0beta1",
            "v8.2RC1",
            "v8.2beta1",
            "v8.1RC2",
            "v8.1.0beta2",
            "v8.1.0beta1",
            "v8.1.0alpha2",
            "v8.1.0alpha1",
            "v8.0.0",
            "v8.0.0RC2",
            "v8.0.0RC1",
            "v8.0.0beta2",
            "v8.0.0beta1",
            "v8.0.0alpha2",
            "v8.0.0alpha1",
            "v7.0.0beta1",
            "v7.0.0alpha2",
            "v6.0.0RC2",
            "v6.0.0RC1",
            "v6.0.0beta5",
            "v6.0.0beta4",
            "v6.0.0beta3",
            "v6.0.0beta2",
            "v6.0.0alpha2",
            "v5.0.0",
            "v5.0.0RC3",
            "v5.0.0RC2",
            "v5.0.0RC1",
            "v5.0.0beta2",
            "v5.0.0beta1",
            "v5.0.0alpha1",
            "v4.5.0",
            "v4.5.0RC3",
            "v4.5.0RC2",
            "v4.5.0RC1",
            "v4.5.0beta4",
            "v4.5.0beta3",
            "v4.0.6",
            "v4.0.5",
            "v4.0.4",
            "v4.0.1",
            "v4.0.0",
            "v4.0.0RC2",
            "v4.0.0RC",
            "v4.0.0beta",
            "v3.0",
            "v1.0.0beta1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-3761.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:49.818045255Z",
      "provider": "osv",
      "references": [
        "https://hackerone.com/reports/343111",
        "https://nextcloud.com/security/advisory/?id=nc-sa-2018-003"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2018-3761",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 437077,
  "published_at": "2018-07-05T16:29:00.407+00:00"
}