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.

CVSS v3.0 7.2 HIGH
CVSS v2.0 9.0 HIGH

7.2^/10

CVSS v3.0 : HIGH

Vector : AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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

9.0^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:S/C:C/I:C/A:C

Exploitability : 8.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

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

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Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:linksys:e1200_firmware:2.0.09:*:*:*:*:*:*:*

cpe:2.3:h:linksys:e1200:-:*:*:*:*:*:*:*

Configuration 2 (hide)

AND

cpe:2.3:o:linksys:e2500_firmware:3.0.04:*:*:*:*:*:*:*

cpe:2.3:h:linksys:e2500:-:*:*:*:*:*:*:*

Information

Published : 2018-10-16 19:29

Updated : 2022-04-19 11:15

NVD link : CVE-2018-3953

Mitre link : CVE-2018-3953

JSON object : View

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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Products Affected

linksys

e1200
e2500
e1200_firmware
e2500_firmware

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