CVE-2026-35444 — SDL_image has a heap buffer overflow READ via unchecked colormap index in XCF loader

Description (CNA)

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 (CNA)

Vendor / product	Versions
libsdl-org / SDL_image	affected < 996bf12888925932daace576e09c3053410896f8

CWE

CWE-125

References

https://github.com/libsdl-org/SDL_image/security/advisories/GHSA-gq8w-x74c-h6p7

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.