Heap-based buffer overflow in Adobe Acrobat Reader 9 before 9.1, 8 before 8.1.4, and 7 before 7.1.1 allows remote attackers to execute arbitrary code via a PDF file with a malformed JBIG2 symbol dictionary segment, a different vulnerability than CVE-2009-1061 and CVE-2009-1062.
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.