CVE-2026-55738

{
  "id": "CVE-2026-55738",
  "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
  "published": "2026-06-17T14:18:00.057",
  "lastModified": "2026-10-26T12:10:00.130",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A stack-based buffer overflow exists in the raw_to_header function in src/microtar.c in rxi microtar 0.1.0. The function copies the 100-byte name and linkname fields of a TAR header with strcpy without guaranteeing null termination of the source."
    },
    {
      "lang": "es",
      "value": "Un desbordamiento de búfer basado en pila existe en la función raw_to_header() en src/microtar.c en rxi microtar 0.1.0. La función copia los campos de 100 bytes name y linkname de una cabecera TAR con strcpy() sin garantizar la terminación nula del origen. El formato POSIX ustar permite que estos campos de ancho fijo se rellenen completamente con bytes no nulos, por lo que un archivo manipulado cuyo campo linkname (seguido por el relleno final de la cabecera raw de 512 bytes) no contiene un terminador nulo hace que strcpy() lea más allá del final del búfer de pila de la cabecera raw de 512 bytes y escriba más allá del búfer de cabecera de destino. Un atacante remoto que suministra un archivo TAR manipulado que la víctima abre o analiza (a través de mtar_open(), mtar_read_header() o mtar_find()) puede causar una lectura fuera de límites y un desbordamiento de búfer de pila, lo que resulta en denegación de servicio (caída) y potencialmente ejecución de código arbitrario. Confirmado con AddressSanitizer: desbordamiento de búfer de pila LECTURA de tamaño 356 en raw_to_header en src/microtar.c:112."
    }
  ],
  "affected": [
    {
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
      "affectedData": [
        {
          "vendor": "rxi",
          "product": "microtar",
          "defaultStatus": "affected",
          "collectionURL": "https://github.com/rxi/microtar",
          "programFiles": [
            "src/microtar.c"
          ],
          "programRoutines": [
            {
              "name": "raw_to_header"
            }
          ],
          "repo": "https://github.com/rxi/microtar",
          "versions": [
            {
              "version": "0.1.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "PASSIVE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-17T15:00:50.582378Z",
          "id": "CVE-2026-55738",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-121"
        },
        {
          "lang": "en",
          "value": "CWE-170"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/rxi/microtar",
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    },
    {
      "url": "https://github.com/rxi/microtar/blob/master/src/microtar.c#L111",
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    },
    {
      "url": "https://raw.githubusercontent.com/rxi/microtar/master/src/microtar.c",
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    }
  ]
}