Buffer overflow in the GMIME_UUENCODE_LEN macro in gmime/gmime-encodings.h in GMime before 2.4.15 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via input data for a uuencode operation.
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.