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BREW-GLANCES-CVE-2020-13757 (GHSA-537H-RV9Q-VVPH)

Vulnerability from osv_homebrew – Published: 2026-08-13 16:51 – Updated: 2026-09-10 19:18 – Source website
VLAI
Summary
Python-RSA decryption of ciphertext leads to DoS
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
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "rsa",
        "resource_purl": "pkg:pypi/rsa@4.9.1",
        "upstream_fixed_in": "4.1"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "glances",
        "purl": "pkg:brew/glances"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/rsa@4.9.1",
        "name": "rsa",
        "resource": "rsa",
        "strategy": "registry",
        "subject_version": "4.9.1"
      }
    ]
  },
  "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": "BREW-glances-CVE-2020-13757",
  "modified": "2026-09-10T19:18:35Z",
  "published": "2026-08-13T16:51:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-13757"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sybrenstuvel/python-rsa/issues/146"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sybrenstuvel/python-rsa/issues/146#issuecomment-641845667"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/rsa/PYSEC-2020-99.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/sybrenstuvel/python-rsa"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2KILTHBHNSDUCYV22ODLOKTICJJ7JQIQ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZYB65VNILRBTXL6EITQTH2PZPK7I23MW"
    },
    {
      "type": "WEB",
      "url": "https://usn.ubuntu.com/4478-1"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Python-RSA decryption of ciphertext leads to DoS",
  "upstream": [
    "GHSA-537h-rv9q-vvph",
    "CVE-2020-13757",
    "PYSEC-2020-99"
  ]
}



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