An issue has been found in third-party PNM decoding associated with libpng prior to 1.6.37. It is a stack-based buffer overflow in the function get_token in pnm2png.c in pnm2png.
CWE-787 - Out-of-Bounds Write
Out-of-bounds write vulnerability is a memory access bug that allows software to write data past the end or before the beginning of the intended buffer. This may result in the corruption of data, a crash, or arbitrary code execution.