CVE-2026-12221

Estado: AplazadaAlta (7.3)—

A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure and is working on a patch to fix it.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/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
Puntuación base: 7.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.37%
Percentil entre todas las CVEs puntuadas: 29
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement75 %
Impacto principalT1059 Command and Scripting Interpreterexecution70 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation65 %

Buffer overflow en servicio remoto (upload de firmware) accesible en red adyacente (AV:A, PR:L). Permite ejecución de código y escalada de privilegios en dispositivo Yealink.

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

Threat Intelligence Program Privileged Account Management Execution Prevention Disable or Remove Feature or Program Application Isolation and Sandboxing Exploit Protection

Tecnologías afectadas (1)

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

Yealink — Sip-t46u^AI

CWE

CWE-119, CWE-121

Referencias

JSON original (NVD)

Mostrar

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          "options": [
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      "affectedData": [
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          "cpes": [
            "cpe:2.3:a:yealink:sip-t46u:*:*:*:*:*:*:*:*"
          ],
          "vendor": "Yealink",
          "modules": [
            "Firmware Chunk Upload Handler"
          ],
          "product": "SIP-T46U",
          "versions": [
            {
              "status": "affected",
              "version": "108.86.0.118"
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  "published": "2026-06-15T06:16:24.263",
  "references": [
    {
      "url": "http://cdn2.v50to.cc/T46U/T46U_mod_upgrade_Upgrade_chunk_stack_overflow.zip",
      "source": "cna@vuldb.com"
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      "url": "https://vuldb.com/cve/CVE-2026-12221",
      "source": "cna@vuldb.com"
    },
    {
      "url": "https://vuldb.com/submit/834207",
      "source": "cna@vuldb.com"
    },
    {
      "url": "https://vuldb.com/vuln/370864",
      "source": "cna@vuldb.com"
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    {
      "url": "https://vuldb.com/vuln/370864/cti",
      "source": "cna@vuldb.com"
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      "source": "cna@vuldb.com",
      "description": [
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          "lang": "en",
          "value": "CWE-119"
        },
        {
          "lang": "en",
          "value": "CWE-121"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability was found in Yealink SIP-T46U 108.86.0.118. This impacts the function sprintf of the file /api/upgrade/upgrade of the component Firmware Chunk Upload Handler. Performing a manipulation of the argument uid/start_offset results in stack-based buffer overflow. The attack needs to be approached within the local network. The exploit has been made public and could be used. The vendor was contacted early about this disclosure and is working on a patch to fix it."
    },
    {
      "lang": "es",
      "value": "Se encontró una vulnerabilidad en Yealink SIP-T46U 108.86.0.118. Esto afecta a la función sprintf del archivo /API/upgrade/upgrade del componente Gestor de Carga de Fragmentos de firmware. Realizar una manipulación del argumento uid/start_offset resulta en un desbordamiento de búfer basado en pila. El ataque debe abordarse dentro de la red local. El exploit se ha hecho público y podría ser utilizado. Se contactó al proveedor con antelación sobre esta divulgación, pero no respondió de ninguna manera."
    }
  ],
  "lastModified": "2026-07-24T12:10:00.210",
  "sourceIdentifier": "cna@vuldb.com"
}