GEN:SID 1:2343
Message FTP STOR overflow attempt
Summary This event is generated when an attempt is made to exploit a buffer
overflow vulnerability associated with WuFtpd STOR command.
Impact Remote access.  A successful attack may permit the remote execution of
arbitrary commands with system privileges.
Detailed Information WuFtpd is an FTP server based on BSD ftpd. A vulnerability exists
with the STOR command that can cause a buffer overflow and permit the
execution of arbitrary commands with system privileges. The buffer
overflow can be caused by supplying an overly long argument to the STOR
command.

The issue exists in the SockPrintf() function. A server using the
MAIL_ADMIN option to send email notifications to the administrator when
files are uploaded to the server, is vulnerable to the attack. It is
possible for an attacker to send malformed data to the store() function
via sockprintf() that will cause the overflow condition to occur, the
error can be generated by the attacker creating a filename greater than
32768 bytes in length.
Affected Systems  
Attack Scenarios An attacker can supply an overly long file argument with the STOR
command, causing a buffer overflow.
Ease of Attack Simple.  
Corrective Action Upgrade to the latest non-affected version of the software.

Use scp as an alternative to ftp

Disallow ftp access to internal resources from external sources

Disable the MAIL_ADMIN option
Additional References  
Rule References bugtraq: 8668
cve: 2000-0133