CVE-2018-3955: linksys e1200_firmware OS Command Injection

Vulnerability summary

CVE-2018-3955 is a high (CVSS 9.0) OS Command Injection vulnerability in linksys e1200_firmware. EPSS estimates a 4.82% chance of exploitation in the next 30 days, higher than 91.9% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 17-10-2018
   PublishedVulnerability first disclosed.
2. 16-09-2024
   Last modifiedVulnerability information updated.

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.

• CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')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.