SparkyFitness is a self-hosted, AI-powered health and fitness tracker for families. Prior to 1.6.0, the api/admin/backup/restore endpoint interpolates an uploaded filename into a shell command. An authenticated global administrator uploads a restore archive with a crafted filename. The administrator can supply a restore archive with a filename containing shell metacharacters. Successful exploitation can execute arbitrary operating-system commands with the server process privileges. This issue is fixed in version 1.6.0.