CVE-2018-3955 Command injection in ESeries E1200

High 7.2 Published 17 Oct 2018 Updated 16 Sep 2024

Authenticated attackers can execute arbitrary system commands via the Domain Name field in Linksys E-Series routers, gaining full device control.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2018-3955?

CVE-2018-3955 is a high-severity command injection vulnerability in Linksys ESeries E1200, published on 17 Oct 2018. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

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.

Weakness: CWE-78

Which versions are affected by CVE-2018-3955?

It affects 2 products.

Products include Linksys E1200 Firmware, Linksys E2500 Firmware.

How do I fix CVE-2018-3955?

No fix has been published for CVE-2018-3955 yet. Limit exposure of the affected software until one is available.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2018-3955 being exploited?

There is no known exploitation of CVE-2018-3955 in the wild and no public exploit code.

Sources

Also known as GHSA-v2p8-7jjc-gfv9.