CVE-2026-5089

{
  "id": "CVE-2026-5089",
  "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
  "published": "2026-05-12T17:16:21.720",
  "lastModified": "2026-10-26T18:10:00.173",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "YAML::Syck versions before 1.38 for Perl  has an out-of-bounds read.\n\nThe base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer:\n\n    while ( colon >= ptr && *colon != ':' )\n    {\n        colon--;\n    }\n    if ( *colon == ':' ) *colon = '\\0';  // colon may be ptr-1 here\n\nWhen no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer."
    },
    {
      "lang": "es",
      "value": "Las versiones de YAML::Syck anteriores a la 1.38 para Perl tienen una lectura fuera de límites.\n\nEl código de análisis (parsing) base60 (sexagesimal) en perl_syck.h tiene un error de subdesbordamiento de búfer en los manejadores int#base60 y float#base60. Al procesar el segmento más a la izquierda de un valor separado por dos puntos (p. ej., el 1 en 1:30:45), el bucle ’while’ interno puede decrementar un puntero más allá del inicio del búfer de cadena:\n\n    while ( colon >= ptr && colon != ’:’ )\n    {\n        colon--;\n    }\n    if ( colon == ’:’ ) colon = ’\\0’;  // ’colon’ puede ser ’ptr-1’ aquí\n\nCuando no se encuentra ningún dos puntos (segmento final/más a la izquierda), ’colon’ se convierte en ’ptr-1’, y la desreferencia subsiguiente de colon lee un byte antes del búfer asignado."
    }
  ],
  "affected": [
    {
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
      "affectedData": [
        {
          "vendor": "TODDR",
          "product": "YAML::Syck",
          "defaultStatus": "unaffected",
          "collectionURL": "https://cpan.org/modules",
          "packageName": "YAML-Syck",
          "programFiles": [
            "perl_syck.h"
          ],
          "repo": "https://github.com/toddr/YAML-Syck",
          "versions": [
            {
              "version": "0",
              "lessThan": "1.38",
              "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:L/A:L",
          "baseScore": 7.3,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-14T13:50:53.123874Z",
          "id": "CVE-2026-5089",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "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-124"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/cpan-authors/YAML-Syck/commit/208a4d3bd1b5cdb4a791a6e3905bd6bd45e9d005.patch",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://github.com/cpan-authors/YAML-Syck/issues/132",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://github.com/cpan-authors/YAML-Syck/pull/133",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "https://metacpan.org/release/TODDR/YAML-Syck-1.38/changes",
      "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"
    },
    {
      "url": "http://www.openwall.com/lists/oss-security/2026/05/12/16",
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://github.com/cpan-authors/YAML-Syck/issues/132",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}