SDL_Image is "an open source library providing image file handling functionality". GIF format handling routines suffers from lack of proper buffer size validating, which makes it vulnerable to a buffer overflow attack. An attacker could DoS an application using SDL_Image, or execute arbitrary code (this has not been confirmed, and is believed to be nontrivial). Since this is a library, in some cases the attack could be remote.
http://www.securiteam.com/unixfocus/5BP0L0UN5Y.html