Several versions of ALEOS, including ALEOS 4.16.0, include an opensource third-party component which can be exploited from the local area network, resulting in a Denial of Service condition for the captive portal.
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
The product writes data past the end, or before the beginning, of the intended buffer.