The Janrain Engage (formerly RPX) module 6.x-1.3 for Drupal does not validate the file for a profile image, which allows remote authenticated users to conduct cross-site scripting (XSS) attacks and possibly execute arbitrary PHP code by causing a crafted avatar to be downloaded from an external login provider site.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.