CVE-2026-71263

Estado: AplazadaCrítica (9.1)—

The LINUXTCP port of FreeModbus contains an off-by-one bounds check in xMBPortTCPPool (demo/LINUXTCP/port/porttcp.c). The check uses a strict greater-than comparison instead of greater-than-or-equal against the 263-byte MB_TCP_BUF_SIZE limit.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Puntuación base: 9.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.50%
Percentil entre todas las CVEs puntuadas: 41
Fecha de la puntuación: 6/10/2026

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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto secundarioT1499.004 Application or System Exploitationimpact60 %

AV:N/AC:L/PR:N indica red sin privilegios (T1190). Off-by-one en buffer de red permite escritura de código (T1059) o negación de servicio (T1499.004) en dispositivo embebido.

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

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Tecnologías afectadas (1)

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

Embedded-solutions — Freemodbus^AI

CWE

CWE-787

Referencias

JSON original (NVD)

Mostrar

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  "id": "CVE-2026-71263",
  "cveTags": [],
  "metrics": {
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-71263",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-08-05T15:39:27.280961Z"
        }
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    "cvssMetricV31": [
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        "cvssData": {
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          "attackVector": "NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "NONE"
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        "impactScore": 5.2,
        "exploitabilityScore": 3.9
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  "affected": [
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      "affectedData": [
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          "vendor": "cwalter-at",
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          "versions": [
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              "version": "0",
              "versionType": "custom",
              "lessThanOrEqual": "*"
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          "programFiles": [
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  "published": "2026-08-05T13:24:50.473",
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      "value": "The LINUXTCP port of FreeModbus contains an off-by-one bounds check in xMBPortTCPPool (demo/LINUXTCP/port/porttcp.c). The check uses a strict greater-than comparison instead of greater-than-or-equal against the 263-byte MB_TCP_BUF_SIZE limit."
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  "lastModified": "2026-08-26T17:13:24.800",
  "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
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