Description
SDL_image is a library to load images of various formats as SDL surfaces. In do_layer_surface() in src/IMG_xcf.c, pixel index values from decoded XCF tile data are used directly as colormap indices without validating them against the colormap size (cm_num). 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 IMAGE_INDEXED 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.
Affected products
libsdl: sdl image
References1
- github.com/libsdl-org/SDL_image/security/advisories/GHSA-gq8w-x… PatchVendor Advisory
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:L - EPSS — exploit probability
- 0% percentile: 19 · as of 12 November 2026
- CWE
- CWE-125
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