gd_xbm.c in the GD Graphics Library (aka libgd) before 2.2.0, as used in certain custom PHP 5.5.x configurations, allows context-dependent attackers to obtain sensitive information from process memory or cause a denial of service (stack-based buffer under-read and application crash) via a long name.
The gdImageScaleTwoPass function in gd_interpolation.c in the GD Graphics Library (aka libgd) before 2.2.0, as used in PHP before 5.6.12, uses inconsistent allocate and free approaches, which allows remote attackers to cause a denial of service (memory consumption) via a crafted call, as demonstrated by a call to the PHP imagescale function.
The GetCode_ function in gd_gif_in.c in GD 2.1.1 and earlier, as used in PHP before 5.5.21 and 5.6.x before 5.6.5, allows remote attackers to cause a denial of service (buffer over-read and application crash) via a crafted GIF image that is improperly handled by the gdImageCreateFromGif function.