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.
An OS command injection vulnerability exists in various legacy D-Link routers—including DIR-300 rev B and DIR-600 (firmware ≤ 2.13 and ≤ 2.14b01, respectively)—due to improper input handling in the unauthenticated command.php endpoint. By sending specially crafted POST requests, a remote attacker can execute arbitrary shell commands with root privileges, allowing full takeover of the device. This includes launching services such as Telnet, exfiltrating credentials, modifying system configuration, and disrupting availability. The flaw stems from the lack of authentication and inadequate sanitation of the cmd parameter.
A vulnerability classified as critical was found in D-Link DAP-1360, DIR-300, DIR-615, DIR-615GF, DIR-615S, DIR-615T, DIR-620, DIR-620S, DIR-806A, DIR-815, DIR-815AC, DIR-815S, DIR-816, DIR-820, DIR-822, DIR-825, DIR-825AC, DIR-825ACF, DIR-825ACG1, DIR-841, DIR-842, DIR-842S, DIR-843, DIR-853, DIR-878, DIR-882, DIR-1210, DIR-1260, DIR-2150, DIR-X1530, DIR-X1860, DSL-224, DSL-245GR, DSL-2640U, DSL-2750U, DSL-G2452GR, DVG-5402G, DVG-5402G, DVG-5402GFRU, DVG-N5402G, DVG-N5402G-IL, DWM-312W, DWM-321, DWR-921, DWR-953 and Good Line Router v2 up to 20240112. This vulnerability affects unknown code of the file /devinfo of the component HTTP GET Request Handler. The manipulation of the argument area with the input notice|net|version leads to information disclosure. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. VDB-251542 is the identifier assigned to this vulnerability.