Breeze Cache < 2.4.5 - Unauthenticated Arbitrary File Upload

Description

The plugin is vulnerable to arbitrary file uploads due to missing file type validation in the 'fetch_gravatar_from_remote' function. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. The vulnerability can only be exploited if "Host Files Locally - Gravatars" is enabled, which is disabled by default.