Re: pop3 exploit????

From: John Thornton (jthorntonat_private)
Date: Mon Oct 15 2001 - 06:09:41 PDT

  • Next message: John Thornton: "Civil Disobedience"

    > I constantly get scanned for the usual services (21, 23, 80,
    > 12345, 27374, etc, etc) and when I scan these systems back the only
    
    As we all do who takes the time to see who is hitting our boxes.
    
    > thing they have in common (as far as running services) is 110 pop3.
    
    One thing to look at is what pop3 daemon the server is running and what
    version it is. I would check securityfocus.com and
    http://icat.nist.gov/icat.cfm ( The icat metabase). More often then not the
    security hole used to exploit the other boxes ispublic. I would have to
    argue that if it was a unknown pop3 daemon exploit they would most likely be
    scanning your box for the same vulnerable service to exploit. So if the
    address you have are blowing pass 110 and looking at ports like  12345,
    27374 and other low level trojan backdoor attacks I would lean more towards
    a coincidence that they have port 110 open.
    
    Now lets say they are all running a pop3 daemon like qpop ( By the way I
    could not connect to any of those ip address you posted on port 110 ) and
    you can't find any known security holes for that version of qpop then in my
    mind it would be worth it to grab that socket programming book and write a
    little server that listens on port 110 and displays the same banner as the
    rest of the attacking servers. Then sniff to see just what in the hell it is
    doing.
    
    With that said, one of the things that I do as a Network Administrator is a
    nslookup on each address that scans my network. This will tell you a lot
    about who is attacking you.
    
    AC9699EE.ipt.aol.com
    cha213245047041.chello.fr
    ua-213-112-62-68.cust.bredbandsbolaget.se
    24-29-125-76.nyc.rr.com
    pD4B894B3.dip.t-dialin.net
    500.POS2-0.SR3.SEA9.ALTER.NET
    p13-0.iplvin1-br1.bbnplanet.net
    
    All of the address that scanned you ( The ones you sent ) belong to a isp of
    some sort. That in it self should tell you that these are low level
    attackers. Most likely these ip address belonged to the attackers home
    computer. In that case what you should do (Sadly not practice enough by the
    Network Admin Community) is to report them to abuseat_private and attach the
    logs of the scan (Make sure you include your time zone, source and
    destination ports used) and let them take care of it. Most likely you and a
    few dozen Network Administrators will report the same address and have Zero
    Cool's service taken away. I have to say, there is nothing like drinking a
    cup a coffee in the morning when checking your email to read that you played
    a role in terminating one less script kids isp. I digress.
    
    Now, if these address translated into something like bob.com, ford.com,
    etc... then that means you might be on to a real live hacker. These are
    _always_ fun to help track down. In that case I would call the network admin
    on the phone, since we would assume the box is owned by a hacker and most
    likely the network admin's mail is being read.
    
    > like this.  I have no clue if these ips are static or dynamic.  This is
    
    Again, a nslookup will tell you a lot, such as if the attacker has a static
    or dynamic address. These are all dynamic ip address.
    
    To sum everything up. Could this be some sort of sophisticated attack of
    some unreported exploit to a pop3 daemon? Hardly. It looks to me like script
    kids and there 'l33t' tools from some 'Hacking' site hosted by tripod. The
    best thing you can do as a Network Administrator is to report these to abuse
    of the isp. However, if the anti-terrorism bill is passed (and it looks that
    way) I would urge you not to. I know I wont. Getting script kids service
    turn off is one thing, having them sent to jail is another...
    
    John Thornton  -  jthorntonat_private
    Editor in Chief
    Hackers Digest -  www.hackersdigest.com
    
    
         H  A  C  K  E  R  '  S    D  I  G  E  S  T
    --------------------------------------------------
    Issue 2 comes out November 1st. Will you get it?
    --------------------------------------------------
                    www.hackersdigest.com
    



    This archive was generated by hypermail 2b30 : Mon Oct 15 2001 - 08:46:45 PDT