Heap-based buffer overflow in the JBIG2 filter in Adobe Reader 7 and Acrobat 7 before 7.1.3, Adobe Reader 8 and Acrobat 8 before 8.1.6, and Adobe Reader 9 and Acrobat 9 before 9.1.2 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via a crafted PDF file that contains JBIG2 text region segments with Huffman encoding.
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.