RE: suspicous activities...

From: Luke Marty (lmarty_at_swiftknowledge.com)
Date: 09/16/04

  • Next message: Jim Harrison (ISA): "RE: unusual 1.11.0.0/16 outbound traffic"
    Date: Thu, 16 Sep 2004 12:06:54 -0500
    To: "hilton de meillon" <hiltond@hotpop.com>, <incidents@securityfocus.com>
    
    

    I have seen a bizillion mails trying to slip through my exchange server
    destined to hanmail.com also. Starting very shortly after I put the mail
    server up. I have since blocked mail to and from that domain at the
    firewall but have not been able isolate where the messages where coming
    from. I assumed it was some sort of bug stuck in my exchange store but
    this makes me a bit more concerned.

    Luke Marty
    Network Shock Trooper
    -----Original Message-----
    From: hilton de meillon [mailto:hiltond@hotpop.com]
    Sent: Tuesday, September 14, 2004 7:23 PM
    To: incidents@securityfocus.com
    Subject: suspicous activities...

    Hi All,
     
    I had this really strange occurrence the other night...
     
    Please find the course of events detailed below :
     
    We had just migrated a clients email (MX) to a new server and as soon as
    we
    switched the MX over the server received thousands of spam emails from
    a domain called hanmail.net (or something like that). Since I was in the
    process of putting the finishing touches on the server I had not
    introduced
    any anti-relay measures (not that anti-relay should have been an
    afterthought) the emails were successfully relayed to other hosts for
    about
    a minute (just until I could re-configure sophos to block that IP from
    relaying.)
     
     
     
    A bit later on I ran chkrootkit and got this message :
     
    (just for reference zzz.yyy.xxx.www is my ip and www.xxx.yyy.zzz is the
    mail
    server.)
     
     
    xyzhost:~# chkrootkit -q
     
    You have 2 process hidden for readdir command
    You have 2 process hidden for ps command
    Warning: Possible LKM Trojan installed
      eth0 is not promisc
     
    so I was like "AAARRRGGGHHH!!!" I then ran :
     
    xyzhost:~# w
     20:38:51 up 59 min, 3 users, load average: 0.07, 0.02, 0.00
    USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
    root pts/0 zzz.yyy.xxx.www 19:40 1:18 0.13s 0.00s tail -f
    /var/log/mail/mail.log
    root pts/1 zzz.yyy.xxx.www 20:06 46.00s 0.28s 0.18s watch
    -n 1
    mailq
    root pts/2 zzz.yyy.xxx.www 20:38 0.00s 0.02s 0.01s w

    I ran chkrootkit again and got this message...

    xyzhost:~# chkrootkit -q
    warning, got bogus tcp line.
      eth0 is not promisc

    Then I ran it again and got nothing...???:
     
    xyzhost:~# chkrootkit -q
      eth0 is not promisc
     
    xyzhost:~# chkrootkit -q
      eth0 is not promisc
     
     
     
    --------------------------------------
     
    Active Internet connections (servers and established)
    Proto Recv-Q Send-Q Local Address Foreign Address
    State
    tcp 0 0 0.0.0.0:110 0.0.0.0:*
    LISTEN
    tcp 0 0 0.0.0.0:143 0.0.0.0:*
    LISTEN
    tcp 0 0 0.0.0.0:80 0.0.0.0:*
    LISTEN
    tcp 0 0 0.0.0.0:22 0.0.0.0:*
    LISTEN
    tcp 0 0 www.xxx.yyy.zzz:25 0.0.0.0:*
    LISTEN
    tcp 0 0 www.xxx.yyy.zzz:22 zzz.yyy.xxx.www:3616
    ESTABLISHED
    tcp 0 0 www.xxx.yyy.zzz:22 zzz.yyy.xxx.www:3489
    ESTABLISHED
    tcp 0 0 www.xxx.yyy.zzz:22 zzz.yyy.xxx.www:3735
    ESTABLISHED
    tcp 1 0 www.xxx.yyy.zzz:33337 211.43.197.159:25
    CLOSE_WAIT
    tcp 0 0 www.xxx.yyy.zzz:33414 203.231.231.41:25
    ESTABLISHED
    Active UNIX domain sockets (servers and established)
    Proto RefCnt Flags Type State I-Node Path
    unix 2 [ ACC ] STREAM LISTENING 15838
    /var/run/mmsmtp.control
    unix 2 [ ACC ] STREAM LISTENING 221
    /var/run/courier/authdaemon/socket.tmp
    unix 7 [ ] DGRAM 155 /dev/log
    unix 2 [ ] DGRAM 299
    unix 2 [ ] DGRAM 253
    unix 2 [ ] DGRAM 245
    unix 2 [ ] DGRAM 220
    unix 2 [ ] DGRAM 198
     
     
    what the hang happened there ??

    The server is a Debian woody running sendmail and sophos mailmonitor
    (mmsmtp
    daemon).

    Any ideas ?.

    Regards,
    Hilton De Meillon.
     
     
     
     


  • Next message: Jim Harrison (ISA): "RE: unusual 1.11.0.0/16 outbound traffic"

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