Security advisory

{
  "id": "746fd9732c720f4c355dd7acc945a12ddb75b29303d553a94fc498ef592e18bd",
  "url": "https://osv.dev/vulnerability/CVE-2017-18594",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2017-18594",
    "summary": "nse_libssh2.cc in Nmap 7.70 is subject to a denial of service condition due to a double free when an SSH connection fails, as demonstrated by a leading \\n character to ssh-brute.nse or ssh-auth-methods.nse.",
    "evidence": "osv:CVE-2017-18594",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2017-18594",
      "aliases": [
        "CVE-2017-18594"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/nmap/nmap",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "350bbe0597d37ad67abe5fef8fba984707b4e9ad"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "fixed": "350bbe0597d37ad67abe5fef8fba984707b4e9ad"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2017-18594.json",
            "vanir_signatures": [
              {
                "id": "CVE-2017-18594-884d6df0",
                "digest": {
                  "length": 602,
                  "function_hash": "181885123553807210789057297674015574442"
                },
                "source": "https://github.com/nmap/nmap/commit/350bbe0597d37ad67abe5fef8fba984707b4e9ad",
                "target": {
                  "file": "nse_libssh2.cc",
                  "function": "do_session_handshake"
                },
                "deprecated": false,
                "signature_type": "Function",
                "signature_version": "v1"
              },
              {
                "id": "CVE-2017-18594-eec30225",
                "digest": {
                  "threshold": 0.9,
                  "line_hashes": [
                    "89047191141271898078379186729701011087",
                    "288418200066937758181363772380073444813",
                    "197504247299643829413881507450264840980",
                    "45853858347866020060594260890860214833",
                    "230612446715307993172166006795828895723",
                    "198393754361702321352110806437967051769",
                    "253764268990083538657657834154227694516",
                    "49832567131233925307305766627838607310",
                    "55587154207647647599364397019466709572",
                    "157468943989143697765082448397421470797",
                    "301199915657737667528034694382631924465"
                  ]
                },
                "source": "https://github.com/nmap/nmap/commit/350bbe0597d37ad67abe5fef8fba984707b4e9ad",
                "target": {
                  "file": "nse_libssh2.cc"
                },
                "deprecated": false,
                "signature_type": "Line",
                "signature_version": "v1"
              }
            ],
            "vanir_signatures_modified": "2026-10-20T13:37:09Z"
          }
        }
      ],
      "modified": "2026-10-20T13:37:09.469980626Z",
      "provider": "osv",
      "references": [
        "https://github.com/AMatchandaHaystack/Research/blob/master/Nmap%26libsshDF",
        "https://seclists.org/nmap-announce/2019/0",
        "https://seclists.org/nmap-dev/2018/q2/45",
        "https://github.com/nmap/nmap/commit/350bbe0597d37ad67abe5fef8fba984707b4e9ad",
        "https://github.com/nmap/nmap/issues/1077",
        "https://github.com/nmap/nmap/issues/1227"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:a:nmap:nmap:7.70:*:*:*:*:*:*:*"
            ],
            "vendor_product": "nmap:nmap",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "7.70"
                  },
                  {
                    "last_affected": "7.70"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2017-18594",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 387894,
  "published_at": "2019-08-29T00:15:10.467+00:00"
}