A vulnerability has been found in Linksys E1200 and E2500 (Router Operating System) (version now known) and classified as critical. This vulnerability affects some unknown processing of the file apply.cgi of the component Network Configuration. The manipulation of the argument Domain Name with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An exploitable operating system command injection exists in the Linksys ESeries line of routers (Linksys E1200 Firmware Version 2.0.09 and Linksys E2500 Firmware Version 3.0.04). Specially crafted entries to network configuration information can cause execution of arbitrary system commands, resulting in full control of the device. An attacker can send an authenticated HTTP request to trigger this vulnerability. Data entered into the 'Domain Name' input field through the web portal is submitted to apply.cgi as the value to the 'wan_domain' POST parameter. The wan_domain data goes through the nvram_set process described above. When the 'preinit' binary receives the SIGHUP signal it enters a code path that calls a function named 'set_host_domain_name' from its libshared.so shared object.

The bug was discovered 10/16/2018. The weakness was presented 10/17/2018 (Website). The advisory is available at talosintelligence.com. This vulnerability was named CVE-2018-3955 since 01/01/2018. The exploitation appears to be easy. The attack can be initiated remotely. Required for exploitation is a single authentication. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1202 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

See 125696 and 125697 for similar entries.

Productinfo

Type

• Router Operating System

Vendor

• Linksys

Name

• E1200
• E2500

License

• commercial

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• 🔍

CPE 2.2info

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• 🔍

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