Heap-based buffer overflow in Xpdf 3.02pl2 and earlier, CUPS 1.3.9, and probably other products, allows remote attackers to execute arbitrary code via a PDF file with crafted JBIG2 symbol dictionary segments.
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.