wu-ftpd, an FTP server, implements a feature whereby multiple files
can be fetched in the form of a dynamically constructed archive file,
such as a tar archive. The names of the files to be included are
passed as command line arguments to tar, without protection against
them being interpreted as command-line options. GNU tar supports
several command line options which can be abused, by means of this
vulnerability, to execute arbitrary programs with the privileges of
the wu-ftpd process.
