Buffer overflow in the GDI engine in Windows Live Messenger, as used for Windows MSN Live 8.1, allows user-assisted remote attackers to cause a denial of service (application crash or system crash) and possibly execute arbitrary code by placing a malformed file in a new folder under the Sharing Folders path, and triggering a synchronize operation through the Windows MSN Live online service, possibly related to extended file attributes and possibly related to an incomplete fix for MS07-046, as demonstrated by a (1) .jpg, (2) .gif, (3) .wmf, (4) .doc, or (5) .ico file.
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.