GEN:SID 1:543
Message POLICY FTP 'STOR 1MB' possible warez site
Summary An attempt to store a file named "1mb" was detected on your ftp
server.
Impact Possible abuse ftp behavior by hordes of warez sites, and the
existance of (potentially) illegal files/software on your ftp server.
Detailed Information Warez sites have been known to name "warez" files by their size.  Large
files are split into smaller, more manageable chunks, and allow warez
sites to store large files on ftp sites in a semi-organized manner.
Affected Systems  
Attack Scenarios As part of an attempt to store elite warez on your ftp server, an
attacker named his/her file "1mb" to indicate it's size.  This file is
likely part of an archive that represents a larger, most likely
illegal copy of media.
Ease of Attack If your ftp server allows write access (presumeably, anonymous), this
is trivial.  
Corrective Action Inspect your ftp server for a file named 1mb.  If it exists, determine
if the file is legitimate, or if it was (yet another) case of a warez
site abusing ftp.  Furthermore, evaluate your need for ftp write
access.
Additional References