Multiple integer overflows in the (1) createwbmp and (2) readwbmp functions in wbmp.c in the GD library (libgd) in PHP 4.0.0 through 4.4.6 and 5.0.0 through 5.2.1 allow context-dependent attackers to execute arbitrary code via Wireless Bitmap (WBMP) images with large width or height values.