An unauthenticated stack-based buffer overflow vulnerability in common.c's handle_PORT in uftpd FTP server versions 2.10 and earlier can be abused to cause a crash and could potentially lead to remote code execution.

In uftpd before 2.12, handle_CWD in ftpcmd.c mishandled the path provided by the user, causing a NULL pointer dereference and denial of service, as demonstrated by a CWD /.. command.

In uftpd before 2.11, it is possible for an unauthenticated user to perform a directory traversal attack using multiple different FTP commands and read and write to arbitrary locations on the filesystem due to the lack of a well-written chroot jail in compose_abspath(). This has been fixed in version 2.11

In uftpd before 2.11, there is a buffer overflow vulnerability in handle_PORT in ftpcmd.c that is caused by a buffer that is 16 bytes large being filled via sprintf() with user input based on the format specifier string %d.%d.%d.%d. The 16 byte size is correct for valid IPv4 addresses (len('255.255.255.255') == 16), but the format specifier %d allows more than 3 digits. This has been fixed in version 2.11