rsync 3.0.0 before 3.5.0 contains a null pointer dereference vulnerability in the daemon child process that allows remote attackers to crash the daemon by sending a file list whose first entry is a dot entry not typed as a directory. The daemon dereferences the first file list entry as a directory structure pointer without verifying the entry type, resulting in an invalid or uninitialized pointer dereference that terminates the client connection.