CVE Vulnerability

CVE-2018-3953

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.

9 /10

CVSS v2.0 :

V3 Legend

Vector :

Exploitability : 8 / Impact : 10

Attack Vector

Attack Complexity

Privileges Required

User Interaction

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

Scope

7.2 /10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References
Link Resource
https://talosintelligence.com/vulnerability_reports/TALOS-2018-0625 Exploit Third Party Advisory
Configurations

Configuration 1
Information

Published : 2018-10-17 02:29

Updated : 2022-04-19 06:15

NVD link : CVE-2018-3953

Mitre link : CVE-2018-3953

Products Affected
No products.
CWE
CWE-78