The fill_xrgb32_lerp_opaque_spans function in cairo-image-compositor.c in cairo before 1.14.2 allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a negative span length.
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.