ubuntu-cve-2020-13757
Vulnerability from osv_ubuntu
Published
2020-06-01 19:15
Modified
2025-10-07 04:47
Summary
Details

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).

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "python-rsa",
            "binary_version": "3.1.2-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "python3-rsa",
            "binary_version": "3.1.2-1ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "python-rsa",
        "purl": "pkg:deb/ubuntu/python-rsa@3.1.2-1ubuntu0.1+esm1?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.1.2-1ubuntu0.1+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.2-1",
        "3.1.2-1ubuntu0.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "python-rsa",
            "binary_version": "3.2.3-1.1ubuntu0.1~esm1"
          },
          {
            "binary_name": "python3-rsa",
            "binary_version": "3.2.3-1.1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "python-rsa",
        "purl": "pkg:deb/ubuntu/python-rsa@3.2.3-1.1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.2.3-1.1ubuntu0.1~esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.4-1",
        "3.2.3-1",
        "3.2.3-1.1"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "python-rsa",
            "binary_version": "3.4.2-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "python3-rsa",
            "binary_version": "3.4.2-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "python-rsa",
        "purl": "pkg:deb/ubuntu/python-rsa@3.4.2-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.4.2-1ubuntu0.1~esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.2-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Python-RSA before 4.1 ignores leading \u0027\\0\u0027 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).",
  "id": "UBUNTU-CVE-2020-13757",
  "modified": "2025-10-07T04:47:28Z",
  "published": "2020-06-01T19:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2020-13757"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/sybrenstuvel/python-rsa/issues/146"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4478-1"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4478-2"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2020-13757"
    }
  ],
  "related": [
    "USN-4478-1",
    "USN-4478-2"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2020-13757"
  ]
}



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