CVE-2026-6103

Estado: Pendiente de análisisMedia (4.3)—

phar_tar_number() parses the octal size field of a TAR header into a uint32_t with no overflow check. The field is 11 octal digits wide and holds values up to 0x1FFFFFFFF, so a size above 0xFFFFFFFF silently wraps. The parser then skips the wrong number of data blocks and interprets attacker-controlled file content as the next TAR header, which lets a crafted archive inject entries that PharData reports and extracts as if they were genuine.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Puntuación base: 4.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.17%
Percentil entre todas las CVEs puntuadas: 5
Fecha de la puntuación: 5/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation45 %
Impacto principalT1565.001 Stored Data Manipulationimpact75 %
Impacto secundarioT1036.005 Match Legitimate Resource Name or Locationstealth60 %

CVE-2026-6103 en PHP permite manipulación de archivos TAR mediante desbordamiento de entero (CWE-190), inyectando entradas falsas sin privilegios elevados. AV:L indica acceso local; el desbordamiento permite evasión de seguridad (I:L). No hay ejecución de código confirmada.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Restrict File and Directory Permissions Execution Prevention Threat Intelligence Program Remote Data Storage Encrypt Sensitive Information Code Signing

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

PHP — PHP^AI

CWE

CWE-190

Referencias

JSON original (NVD)

Mostrar

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  "cveTags": [],
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-6103",
          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-09-25T20:41:05.626504Z"
        }
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          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N",
          "integrityImpact": "LOW",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 1.4,
        "exploitabilityScore": 2.5
      }
    ]
  },
  "affected": [
    {
      "source": "security@php.net",
      "affectedData": [
        {
          "vendor": "PHP Group",
          "product": "PHP",
          "versions": [
            {
              "status": "affected",
              "version": "8.2.*",
              "lessThan": "8.2.34",
              "versionType": "semver"
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            {
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  "published": "2026-09-25T21:17:23.790",
  "references": [
    {
      "url": "https://github.com/php/php-src/security/advisories/GHSA-j3wh-g957-2m85",
      "source": "security@php.net"
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    {
      "lang": "en",
      "value": "phar_tar_number() parses the octal size field of a TAR header into a uint32_t with no overflow check. The field is 11 octal digits wide and holds values up to 0x1FFFFFFFF, so a size above 0xFFFFFFFF silently wraps. The parser then skips the wrong number of data blocks and interprets attacker-controlled file content as the next TAR header, which lets a crafted archive inject entries that PharData reports and extracts as if they were genuine."
    }
  ],
  "lastModified": "2026-09-29T21:27:41.130",
  "sourceIdentifier": "security@php.net"
}