CVE-2018-3953

Estado: ModificadaAlta (7.2)—

Devices in the Linksys ESeries line of routers (Linksys E1200 Firmware Version 2.0.09 and Linksys E2500 Firmware Version 3.0.04) are susceptible to OS command injection vulnerabilities due to improper filtering of data passed to and retrieved from NVRAM. Data entered into the 'Router Name' input field through the web portal is submitted to apply.cgi as the value to the 'machine_name' POST parameter. When the 'preinit' binary receives the SIGHUP signal, it enters a code path that continues until it reaches offset 0x0042B5C4 in the 'start_lltd' function.

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Within the 'start_lltd' function, a 'nvram_get' call is used to obtain the value of the user-controlled 'machine_name' NVRAM entry. This value is then entered directly into a command intended to write the host name to a file and subsequently executed.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.2

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 14%
Percentil entre todas las CVEs puntuadas: 96
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).

Tecnologías afectadas (2)

Linksys — E1200 Firmware Linksys — E2500 Firmware

CWE

CWE-78

Referencias

JSON original (NVD)

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  "vulnStatus": "Modified",
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      "value": "Devices in the Linksys ESeries line of routers (Linksys E1200 Firmware Version 2.0.09 and Linksys E2500 Firmware Version 3.0.04) are susceptible to OS command injection vulnerabilities due to improper filtering of data passed to and retrieved from NVRAM. Data entered into the 'Router Name' input field through the web portal is submitted to apply.cgi as the value to the 'machine_name' POST parameter. When the 'preinit' binary receives the SIGHUP signal, it enters a code path that continues until it reaches offset 0x0042B5C4 in the 'start_lltd' function. Within the 'start_lltd' function, a 'nvram_get' call is used to obtain the value of the user-controlled 'machine_name' NVRAM entry. This value is then entered directly into a command intended to write the host name to a file and subsequently executed."
    },
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      "value": "Los dispositivos de la línea de routers Linksys ESeries (Linksys E1200 con versión del firmware 2.0.09 y Linksys E2500 con versión del firmware 3.0.04) son susceptibles a vulnerabilidades de inyección de comandos debido al filtrado incorrecto de datos pasados y recuperados desde el NVRAM. Los datos introducidos en el campo de entrada \"Router Name\" mediante el portal web se envían a apply.cgi como el valor del parámetro POST \"machine_name\". Cuando el binario \"preinit\" recibe la señal SIGHUP, introduce una ruta de código que continúa hasta que alcanza el offset 0x0042B5C4 en la función \"start_lltd\". En la función \"start_lltd\", se emplea una llamada \"nvram_get\" para obtener el valor de la entrada NVRAM \"machine_name\" controlada por el usuario. Este valor se introduce en un comando que debe escribir el nombre del host en un archivo y después se ejecuta."
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  "lastModified": "2026-06-17T01:58:06.313",
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