CVE-2018-3953

Severity Score

7.2

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

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.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

Single

Confidentiality

Complete

Integrity

Complete

Availability

Complete

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2018-01-02 CVE Reserved
2018-10-17 CVE Published
2024-07-31 EPSS Updated
2024-09-17 CVE Updated
2024-09-17 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CAPEC

References (1)

URL	Tag	Source

URL	Date	SRC
https://talosintelligence.com/vulnerability_reports/TALOS-2018-0625	2024-09-17

URL	Date	SRC

URL	Date	SRC

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Linksys Search vendor "Linksys"	E1200 Firmware Search vendor "Linksys" for product "E1200 Firmware"	2.0.09 Search vendor "Linksys" for product "E1200 Firmware" and version "2.0.09"	-	Affected	in	Linksys Search vendor "Linksys"	E1200 Search vendor "Linksys" for product "E1200"	-	-	Safe
Linksys Search vendor "Linksys"	E2500 Firmware Search vendor "Linksys" for product "E2500 Firmware"	3.0.04 Search vendor "Linksys" for product "E2500 Firmware" and version "3.0.04"	-	Affected	in	Linksys Search vendor "Linksys"	E2500 Search vendor "Linksys" for product "E2500"	-	-	Safe