Linksys E1000 devices through 2.1.02, E1200 devices before 2.0.05, and E3200 devices through 1.0.04 allow OS command injection via shell metacharacters in the apply.cgi ping_ip parameter on TCP port 52000.

Linksys Routers E/WAG/WAP/WES/WET/WRT-Series

An OS command injection vulnerability exists in various models of E-Series Linksys routers via the /tmUnblock.cgi and /hndUnblock.cgi endpoints over HTTP on port 8080. The CGI scripts improperly process user-supplied input passed to the ttcp_ip parameter without sanitization, allowing unauthenticated attackers to inject shell commands. This vulnerability was reported to be exploited in the wild by the "TheMoon" worm  in 2014 to deploy a MIPS ELF payload, enabling arbitrary code execution on the router. Additionally, this vulnerability may affect other Linksys products to include, but not limited to, WAG/WAP/WES/WET/WRT-series router models and Wireless-N access points and routers. Exploitation evidence was observed by the Shadowserver Foundation on 2025-02-06 UTC.

There is stack-based buffer overflow vulnerability in pc_change_act function in Linksys E1000 router firmware version v.2.1.03 and before, leading to remote code execution.