Security advisory

{
  "id": "d0c094e900f286b11405d41e0e1a49956679322b548a63af91fc62077daf012c",
  "url": "https://osv.dev/vulnerability/CVE-2018-6594",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2018-6594",
    "summary": "lib/Crypto/PublicKey/ElGamal.py in PyCrypto through 2.6.1 generates weak ElGamal key parameters, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for PyCrypto's ElGamal implementation.",
    "evidence": "osv:CVE-2018-6594",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2018-6594",
      "aliases": [
        "CVE-2018-6594",
        "GHSA-6528-wvf6-f6qg",
        "PYSEC-2018-97"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/pycrypto/pycrypto",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "7fd528d03b5eae58eef6fd219af5d9ac9c83fa50"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:dlitz:pycrypto:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "last_affected": "2.6.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.6.1",
            "v2.6",
            "v2.5",
            "v2.4.1",
            "v2.4",
            "v2.3",
            "v2.2",
            "v2.1.0",
            "v2.1.0b1",
            "v2.1.0alpha2",
            "v2.1.0alpha1",
            "v1.9a5",
            "v1.9a4",
            "v1.9a3",
            "v1.9a2",
            "v1.9a1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-6594.json"
          }
        }
      ],
      "modified": "2026-10-20T10:51:34.909382552Z",
      "provider": "osv",
      "references": [
        "https://github.com/TElgamal/attack-on-pycrypto-elgamal",
        "https://lists.debian.org/debian-lts-announce/2018/02/msg00018.html",
        "https://security.gentoo.org/glsa/202007-62",
        "https://usn.ubuntu.com/3616-1/",
        "https://usn.ubuntu.com/3616-2/",
        "https://github.com/dlitz/pycrypto/issues/253"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*",
              "cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*",
              "cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*",
              "cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*"
            ],
            "vendor_product": "canonical:ubuntu_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "12.04"
                  },
                  {
                    "last_affected": "12.04"
                  },
                  {
                    "introduced": "14.04"
                  },
                  {
                    "last_affected": "14.04"
                  },
                  {
                    "introduced": "16.04"
                  },
                  {
                    "last_affected": "16.04"
                  },
                  {
                    "introduced": "17.10"
                  },
                  {
                    "last_affected": "17.10"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          },
          {
            "cpes": [
              "cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*"
            ],
            "vendor_product": "debian:debian_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "7.0"
                  },
                  {
                    "last_affected": "7.0"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2018-6594",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 382600,
  "published_at": "2018-02-03T15:29:00.653+00:00"
}