Affected: D-Link DIR-600 rev B, D-Link DIR-300 rev B

The web interface of multiple D-Link routers, including DIR-600 rev B (≤2.14b01) and DIR-300 rev B (≤2.13), contains an unauthenticated OS command injection vulnerability in command.php, which improperly handles the cmd POST parameter. A remote attacker can exploit this flaw without authentication to spawn a Telnet service on a specified port, enabling persistent interactive shell access as root.