Security advisory

{
  "id": "fc15303b82ba206e25d58a56b245f90836e361382921482594e9c1851db08ce0",
  "url": "https://osv.dev/vulnerability/CVE-2018-8899",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-8899",
    "summary": "IdentityServer IdentityServer4 1.x before 1.5.3 and 2.x before 2.1.3 does not encode the redirect URI on the authorization response page, which might lead to XSS in some configurations.",
    "evidence": "osv:CVE-2018-8899",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2018-8899",
      "aliases": [
        "CVE-2018-8899"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/DuendeArchive/IdentityServer4",
              "type": "GIT",
              "events": [
                {
                  "introduced": "62eea365e8835323230c32eff6ec9b7b78cc1be0"
                },
                {
                  "last_affected": "b9f179103be2d8708131394527cebc1e9f6b17aa"
                },
                {
                  "introduced": "1b88084c06eb6a0368ccec9fed7c9a295f1d508b"
                },
                {
                  "last_affected": "becb2206826b1039687b3ec895fad5e1b26ef0c5"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:identityserver:identityserver4:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "last_affected": "1.5.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:identityserver:identityserver4:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.0.0"
                      },
                      {
                        "last_affected": "2.1.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.1.2",
            "2.1.1",
            "2.1.0",
            "2.0.6",
            "2.0.5",
            "2.0.4",
            "2.0.3",
            "2.0.2",
            "2.0.1",
            "2.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-8899.json"
          }
        },
        {
          "ranges": [
            {
              "repo": "https://github.com/duendearchive/identityserver4",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "21d0da227f50ac102de469a13bc5a15d2cc0f895"
                },
                {
                  "fixed": "02e7b1db08ea20483fa84f0087612f9d7c57d7e7"
                },
                {
                  "fixed": "35ac1ac2d8f62cc3c6b2602bb653c3e651cdcfd8"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "fixed": "21d0da227f50ac102de469a13bc5a15d2cc0f895"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "02e7b1db08ea20483fa84f0087612f9d7c57d7e7"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "1.5.3"
                  },
                  {
                    "range": [
                      {
                        "fixed": "35ac1ac2d8f62cc3c6b2602bb653c3e651cdcfd8"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "2.1.3"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.1.2",
            "2.1.1",
            "2.1.0",
            "2.0.6",
            "2.0.5",
            "2.0.4",
            "2.0.3",
            "2.0.2",
            "2.0.1",
            "2.0.0",
            "2.0.0-rc1-update1",
            "2.0.0-rc1",
            "1.5.0",
            "1.4.2",
            "1.4.1",
            "1.3.1",
            "1.3.0",
            "1.2.1",
            "1.2.0",
            "1.2",
            "1.1.1",
            "1.1.0",
            "1.0.2",
            "1.0.1",
            "1.0.0-rc4",
            "1.0.0-rc3",
            "1.0.0-rc2",
            "1.0.0-rc1-update2",
            "1.0.0-rc1-update1",
            "1.0.0-rc1",
            "beta5",
            "beta4-update2",
            "beta4-update1",
            "beta4",
            "beta3",
            "beta2-update2",
            "beta2",
            "beta1-update1",
            "1.0.0-beta1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-8899.json"
          }
        }
      ],
      "modified": "2026-10-20T10:49:30.170651978Z",
      "provider": "osv",
      "references": [
        "https://github.com/IdentityServer/IdentityServer4/releases/tag/1.5.3",
        "https://github.com/IdentityServer/IdentityServer4/releases/tag/2.1.3",
        "https://github.com/IdentityServer/IdentityServer4/issues/2164",
        "https://github.com/IdentityServer/IdentityServer4/commit/21d0da227f50ac102de469a13bc5a15d2cc0f895"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2018-8899",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 380477,
  "published_at": "2018-03-22T05:29:00.287+00:00"
}