Heap-based buffer overflow in the xmlParseXmlDecl function in parser.c in libxml2 before 2.9.3 allows context-dependent attackers to cause a denial of service via unspecified vectors related to extracting errors after an encoding conversion failure.
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.