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brew-ansible@10-cve-2018-10903
Vulnerability from osv_homebrew
Published
2026-08-13 16:35
Modified
2026-09-09 23:41
Summary
PyCA Cryptography vulnerable to GCM tag forgery
Details

A flaw was found in python-cryptography versions between >=1.9.0 and <2.3. The finalize_with_tag API did not enforce a minimum tag length. If a user did not validate the input length prior to passing it to finalize_with_tag an attacker could craft an invalid payload with a shortened tag (e.g. 1 byte) such that they would have a 1 in 256 chance of passing the MAC check. GCM tag forgeries can cause key leakage.

Severity
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "cryptography",
        "resource_purl": "pkg:pypi/cryptography@46.0.3",
        "upstream_fixed_in": "2.3"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "ansible@10",
        "purl": "pkg:brew/ansible%4010"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.7.0_6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/cryptography@46.0.3",
        "name": "cryptography",
        "resource": "cryptography",
        "strategy": "registry",
        "subject_version": "46.0.3"
      }
    ]
  },
  "details": "A flaw was found in python-cryptography versions between \u003e=1.9.0 and \u003c2.3. The finalize_with_tag API did not enforce a minimum tag length. If a user did not validate the input length prior to passing it to finalize_with_tag an attacker could craft an invalid payload with a shortened tag (e.g. 1 byte) such that they would have a 1 in 256 chance of passing the MAC check. GCM tag forgeries can cause key leakage.",
  "id": "BREW-ansible@10-CVE-2018-10903",
  "modified": "2026-09-09T23:41:05Z",
  "published": "2026-08-13T16:35:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-10903"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pyca/cryptography/pull/4342"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pyca/cryptography/commit/d4378e42937b56f473ddade2667f919ce32208cb"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2018:3600"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10903"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-fcf9-3qw3-gxmj"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pyca/cryptography"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/cryptography/PYSEC-2018-52.yaml"
    },
    {
      "type": "WEB",
      "url": "https://usn.ubuntu.com/3720-1"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "PyCA Cryptography vulnerable to GCM tag forgery",
  "upstream": [
    "GHSA-fcf9-3qw3-gxmj",
    "CVE-2018-10903",
    "PYSEC-2018-52"
  ]
}



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