A buffer overflow vulnerability (CVE-2026-7750) has been identified in Totolink N300RH router firmware version 3.2.4-B20220812. The vulnerability affects the setMacFilterRules function in /cgi-bin/cstecgi.cgi of the POST Request Handler component. Attackers can exploit this by manipulating the mac_address argument to cause a buffer overflow. The vulnerability can be exploited remotely and public exploits are now available, making this a high-severity security risk for affected devices.