A stack-based buffer overflow vulnerability affects the mtk_dut binary in Linksys E7350 routers running Firmware 1.1.00.032. The vulnerability arises because the function sub_4045A8 reads up to 256 bytes from a system file into a local buffer and then copies it without boundary checks into a smaller caller-provided buffer. This can lead to memory corruption, denial of service, or potential arbitrary code execution if exploited by a local attacker controlling the file contents.