Stack-based buffer overflow in the loadit function in plug-ins/common/sphere-designer.c in the SPHERE DESIGNER plugin in GIMP 2.6.11 allows user-assisted remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a long "Number of lights" field in a plugin configuration file.  NOTE: it may be uncommon to obtain a GIMP plugin configuration file from an untrusted source that is separate from the distribution of the plugin itself.