Security advisory

{
  "id": "3f7e6d23015ffd130fca82caa760781c8a69df2172bf3fe36f18d0d5704bfe57",
  "url": "https://osv.dev/vulnerability/CVE-2021-25762",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2021-25762",
    "summary": "In JetBrains Ktor before 1.4.3, HTTP Request Smuggling was possible.",
    "evidence": "osv:CVE-2021-25762",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2021-25762",
      "aliases": [
        "CVE-2021-25762"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/ktorio/ktor",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "e28148d34b87ccd94fb1ef0c21742826619ea444"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:jetbrains:ktor:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.4.3"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.4.2",
            "1.4.1",
            "1.4.0",
            "1.3.2",
            "1.3.1",
            "1.3.0",
            "1.3.0-rc2",
            "1.3.0-rc",
            "1.3.0-beta-2",
            "1.3.0-beta-1",
            "1.2.3",
            "1.2.3-rc",
            "1.2.2",
            "1.2.1",
            "1.2.0",
            "1.2.0-rc2",
            "1.2.0-rc",
            "1.2.0-alpha-2",
            "1.2.0-alpha-1",
            "1.1.2",
            "1.1.1",
            "1.1.0",
            "1.0.1",
            "1.0.0",
            "1.0.0-rc",
            "1.0.0-beta-4",
            "1.0.0-beta-3",
            "1.0.0-beta-2",
            "1.0.0-beta-1",
            "1.0.0-alpha-3",
            "1.0.0-alpha-2",
            "1.0.0-alpha-1",
            "0.9.5",
            "0.9.4",
            "0.9.4-dev-3",
            "0.9.4-alpha-2",
            "0.9.3-alpha-4",
            "0.9.3-alpha-3",
            "0.9.3-alpha-2",
            "0.9.3-alpha-1",
            "0.9.2",
            "0.9.2-alpha-6",
            "0.9.2-alpha-5",
            "0.9.2-alpha-4",
            "0.9.2-alpha-3",
            "0.9.2-alpha-2",
            "0.9.2-alpha-1",
            "0.9.1",
            "0.9.1-alpha-10",
            "0.9.1-alpha-9",
            "0.9.1-alpha-8",
            "0.9.1-alpha-7",
            "0.9.1-alpha-6",
            "0.9.1-alpha-5",
            "0.9.1-alpha-4",
            "0.9.0",
            "0.9.0-alpha-3",
            "0.9.0-alpha-2",
            "build-0.4.1-alpha-16",
            "ktor-0.4.0",
            "build-0.4.0-alpha-15",
            "build-0.4.0-alpha-14",
            "build-0.4.0-alpha-13",
            "build-0.4.0-alpha-12",
            "build-0.4.0-alpha-11",
            "build-0.4.0-alpha-10",
            "build-0.4.0-alpha-9",
            "build-0.4.0-alpha-8",
            "build-0.4.0-alpha-7",
            "build-0.4.0-alpha-6",
            "ktor-0.3.3",
            "ktor-0.3.2",
            "ktor-0.3.1",
            "ktor-0.3.0",
            "ktor-0.2.4",
            "ktor-0.2.3",
            "ktor-0.2.2",
            "ktor-0.2.1",
            "ktor-0.2.0",
            "ktor-0.1.8",
            "ktor-0.1.7",
            "ktor-0.1.6",
            "ktor-0.1.5",
            "ktor-0.1.4",
            "ktor-0.1.3",
            "ktor-0.1.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-25762.json"
          }
        }
      ],
      "modified": "2026-10-24T10:30:18.899204184Z",
      "provider": "osv",
      "references": [
        "https://blog.jetbrains.com/blog/2021/02/03/jetbrains-security-bulletin-q4-2020/",
        "https://blog.jetbrains.com"
      ],
      "provider_metadata": {}
    },
    "related_cves": [
      {
        "value": "CVE-2021-25762",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 429883,
  "published_at": "2021-02-03T16:15:14.713+00:00"
}