Multiple heap-based buffer overflows in the parse_notify function in sgminer before 4.2.2, cgminer before 4.3.5, and BFGMiner before 4.1.0 allow remote pool servers to have unspecified impact via a (1) large or (2) negative value in the Extranonc2_size parameter in a mining.subscribe response and a crafted mining.notify request.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.