SDLimage is a library to load images of various formats as SDL surfaces. In dolayersurface() in src/IMGxcf.c, pixel index values from decoded XCF tile data are used directly as colormap indices without validating them against the colormap size (cmnum). A crafted .xcf file with a small colormap and out-of-range pixel indices causes heap out-of-bounds reads of up to 762 bytes past the colormap allocation. Both IMAGEINDEXED code paths are affected (bpp=1 and bpp=2). The leaked heap bytes are written into the output surface pixel data, making them potentially observable in the rendered image. This vulnerability is fixed with commit 996bf12888925932daace576e09c3053410896f8.

An exploitable code execution vulnerability exists in the ILBM image rendering functionality of SDL2image-2.0.2. A specially crafted ILBM image can cause a heap overflow resulting in code execution. An attacker can display a specially crafted image to trigger this vulnerability.