Multiple buffer overflows in the JBIG2 decoder in Xpdf 3.02pl2 and earlier, CUPS 1.3.9 and earlier, and other products allow remote attackers to cause a denial of service (crash) via a crafted PDF file, related to (1) JBIG2SymbolDict::setBitmap and (2) JBIG2Stream::readSymbolDictSeg.
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.