An issue was discovered in Tenda W20E V4.0br_V15.11.0.6. Attackers may send overly long `addDhcpRules` data. When these rules enter the `addDhcpRule` function a…

A buffer overflow vulnerability was discovered in Tenda W20E router firmware V15.11.0.6. The vulnerability exists in the addDhcpRule function where attackers can send overly long addDhcpRules data. The sscanf function processes this data without proper size validation, leading to buffer overflows in dhcpsIndex, dhcpsIP, and dhcpsMac variables. This lack of input validation could allow attackers to exploit the DHCP rule processing functionality.