CVE-2026-13577

{
  "id": "CVE-2026-13577",
  "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
  "published": "2026-07-20T08:16:28.987",
  "lastModified": "2026-10-24T20:10:00.137",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Dancer2 versions before 2.2.0 for Perl generate insecure session ids when required CSPRNG modules are unavailable.\n\nDancer2::Core::Role::SessionFactory::generate_id silently falls back to a built-in rand-derived session id unless both Math::Random::ISAAC::XS and Crypt::URandom are available.\n\nThe fallback session id is generated from a SHA-1 hash of a call to the built-in rand function, the absolute path of the Dancer2::Core::Role::SessionFactory module, an internal counter, the process id, the module instance memory address, and a shuffled string of characters (using the List::Util::shuffle function, which also uses the built-in rand function).\n\nThese are all low-entropy and easily guessed sources.\n\nThe built-in rand() function is seeded with 32-bits and considered unsuitable for security applications.\n\nPredictable session ids could allow an attacker to gain access to systems."
    },
    {
      "lang": "es",
      "value": "Las versiones de Dancer2 hasta la 2.1.0 para Perl generan identificadores de sesión inseguros cuando los módulos CSPRNG requeridos no están disponibles.\n\nDancer2::Core::Role::SessionFactory::generate_id recurre silenciosamente a un identificador de sesión derivado de la función ’rand’ incorporada a menos que Math::Random::ISAAC::XS y Crypt::URandom estén ambos disponibles.\n\nEl identificador de sesión de respaldo se genera a partir de un hash SHA-1 de una llamada a la función ’rand’ incorporada, la ruta absoluta del módulo Dancer2::Core::Role::SessionFactory, un contador interno, el ID del proceso, la dirección de memoria de la instancia del módulo y una cadena de caracteres mezclada (utilizando la función List::Util::shuffle, que también usa la función ’rand’ incorporada).\n\nTodas estas son fuentes de baja entropía y fácilmente predecibles.\n\nLa función ’rand()’ incorporada se inicializa con 32 bits y se considera inadecuada para aplicaciones de seguridad.\n\nLos identificadores de sesión predecibles podrían permitir a un atacante obtener acceso a los sistemas."
    }
  ],
  "affected": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "collectionURL": "https://cpan.org/modules",
          "packageName": "Dancer2",
          "modules": [
            "Dancer2"
          ],
          "programFiles": [
            "lib/Dancer2/Core/Role/SessionFactory.pm"
          ],
          "programRoutines": [
            {
              "name": "Dancer2::Core::Role::SessionFactory::generate_id"
            }
          ],
          "repo": "https://github.com/PerlDancer/Dancer2",
          "packageURL": "pkg:cpan/Dancer2",
          "versions": [
            {
              "version": "0",
              "lessThan": "2.2.0",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-20T13:05:03.182340Z",
          "id": "CVE-2026-13577",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-338"
        },
        {
          "lang": "en",
          "value": "CWE-340"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/PerlDancer/Dancer2/blob/v2.1.0/lib/Dancer2/Core/Role/SessionFactory.pm#L142",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://github.com/PerlDancer/Dancer2/issues/1807",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://github.com/PerlDancer/Dancer2/pull/1804",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://metacpan.org/release/CROMEDOME/Dancer2-2.2.0/changes",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-5080",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    }
  ]
}