Stack-based buffer overflow in converter/ppm/xpmtoppm.c in netpbm before 10.47.07 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via an XPM image file that contains a crafted header field associated with a large color index value.
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.