CVE-2018-3953

Published Oct 17, 2018

Last updated 4 days ago

Overview

Description
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.
Source
talos-cna@cisco.com
NVD status
Modified

Risk scores

CVSS 3.1

Type
Primary
Base score
7.2
Impact score
5.9
Exploitability score
1.2
Vector string
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

CVSS 3.0

Type
Secondary
Base score
7.2
Impact score
5.9
Exploitability score
1.2
Vector string
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
9
Impact score
10
Exploitability score
8
Vector string
AV:N/AC:L/Au:S/C:C/I:C/A:C

Weaknesses

nvd@nist.gov
CWE-78

Social media

Hype score
Not currently trending

Configurations