Security advisory

{
  "id": "ae3049510378cae765a5fa72e0f04cf904bab04e49b90f850d88aaf38d7dda3d",
  "url": "https://osv.dev/vulnerability/CVE-2020-13757",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "CVE-2020-13757",
    "summary": "Python-RSA before 4.1 ignores leading '\\0' bytes during decryption of ciphertext. This could conceivably have a security-relevant impact, e.g., by helping an attacker to infer that an application uses Python-RSA, or if the length of accepted ciphertext affects application behavior (such as by causing excessive memory allocation).",
    "evidence": "osv:CVE-2020-13757",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2020-13757",
      "aliases": [
        "CVE-2020-13757",
        "GHSA-537h-rv9q-vvph",
        "PYSEC-2020-99"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/sybrenstuvel/python-rsa",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "c6731b1dda461676b998a18004b23a9879378041"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:python-rsa_project:python-rsa:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "4.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "version-4.0",
            "version-3.4",
            "version-3.3",
            "version-3.2.3",
            "version-3.2.2",
            "version-3.2.1",
            "version-3.2",
            "version-3.1.4",
            "version-3.1.3",
            "version-3.1.2",
            "version-3.1.1",
            "version-3.1",
            "version-3.0.1",
            "version-3.0",
            "version-2.0",
            "version-1.3.3",
            "version-1.3.2",
            "version-1.3.1",
            "version-1.3",
            "version-1.2",
            "version-1.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-13757.json"
          }
        }
      ],
      "modified": "2026-10-20T10:51:48.140966581Z",
      "provider": "osv",
      "references": [
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2KILTHBHNSDUCYV22ODLOKTICJJ7JQIQ/",
        "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZYB65VNILRBTXL6EITQTH2PZPK7I23MW/",
        "https://usn.ubuntu.com/4478-1/",
        "https://github.com/sybrenstuvel/python-rsa/issues/146",
        "https://github.com/sybrenstuvel/python-rsa/issues/146#issuecomment-641845667"
      ],
      "provider_metadata": {
        "unresolved_ranges": [
          {
            "cpes": [
              "cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*"
            ],
            "vendor_product": "canonical:ubuntu_linux",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "14.04"
                  },
                  {
                    "last_affected": "14.04"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          },
          {
            "cpes": [
              "cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*",
              "cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*"
            ],
            "vendor_product": "fedoraproject:fedora",
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "31"
                  },
                  {
                    "last_affected": "31"
                  },
                  {
                    "introduced": "32"
                  },
                  {
                    "last_affected": "32"
                  }
                ],
                "source": "CPE_STRING"
              }
            ]
          }
        ]
      }
    },
    "related_cves": [
      {
        "value": "CVE-2020-13757",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 382961,
  "published_at": "2020-06-01T19:15:10.067+00:00"
}