COMMAND

    wu.ftpd(8)

SYSTEMS AFFECTED

    Some sites running wuarchive ftpd v2.2 and v2.1f.

PROBLEM

    Some  copies  of  the  source  code  for  versions 2.2 and 2.1f of
    the  wuarchive  ftpd  were  modified  by  an intruder, and contain
    a  Trojan  horse.  If  your  FTP  daemon  was  compiled  from  the
    intruder-modified  source  code,  you  are  vulnerable.  To verify
    this grep the source  code for '"NULL"', if  you find it you  have
    a trojan.

SOLUTION

    Grab the latest version and compile it.