The Program::getUniformInternal function in Program.cpp in libANGLE, as used in Google Chrome before 49.0.2623.108, does not properly handle a certain data-type mismatch, which allows remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via crafted shader stages.
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.