Re: CodeRed Observations.

From: Q=F3rhallur_H=E1lfd=E1narson?= (tolli@tol.li)
Date: 03/14/03

  • Next message: larosa, vjay: "RE: CodeRed Observations."
    Date: Thu, 13 Mar 2003 23:22:54 +0000
    From: Q=F3rhallur_H=E1lfd=E1narson?= <tolli@tol.li>
    To: "larosa, vjay" <larosa_vjay@emc.com>
    
    

    Hi

    When you notice these packets, are there *never* SYN packets?

    I'm thinking: firewall at other end blocking only SYN outbound (quite unlikely if you're getting it by hundreds, but, hey, one never knows :)

    Regards,
    Tolli

    -*- larosa, vjay <larosa_vjay@emc.com> [ 2003-03-13 18:28 ]:
    > Some of the systems respond to a ping, none respond to
    > any HTTP requests. It doesn't mean that they are not
    > firewalled from incoming traffic though.
    >
    > vjl
    >
    > -----Original Message-----
    > From: Rob Shein [mailto:shoten@starpower.net]
    > Sent: Thursday, March 13, 2003 12:13 PM
    > To: 'larosa, vjay'; incidents@securityfocus.com
    > Subject: RE: CodeRed Observations.
    >
    >
    > Ok, here's another thought...is the IP address that the traffic apparently
    > originates from actually accessible, and is it running a vulnerable IIS? I
    > would think that if someone wanted to hide an attack, they'd hide amidst a
    > huge amount of varied attack noise, rather than something so homogenous (and
    > expected) as this.
    >
    > > -----Original Message-----
    > > From: larosa, vjay [mailto:larosa_vjay@emc.com]
    > > Sent: Thursday, March 13, 2003 11:59 AM
    > > To: 'Rob Shein'; larosa, vjay; incidents@securityfocus.com
    > > Subject: RE: CodeRed Observations.
    > >
    > >
    > > Hi Rob,
    > >
    > > I'm not saying that the worm is stateless. I am saying that
    > > the traffic I am seeing at my border firewalls (codered
    > > strings) are not part of established sessions (stateless). I
    > > was just trying
    > > to figure out if this had something to do with the new
    > > outbreak, or if
    > > somebody is trying to trick me in to ignoring packets they
    > > don't want me to see, so they are throwing a stateless attack
    > > at me to hopefully hide the real attack under the guise of
    > > CodeRed. Call me crazy but paranoia is my middle name.
    > >
    > > vjl
    > >
    > >
    > > -----Original Message-----
    > > From: Rob Shein [mailto:shoten@starpower.net]
    > > Sent: Thursday, March 13, 2003 11:50 AM
    > > To: 'larosa, vjay'; incidents@securityfocus.com
    > > Subject: RE: CodeRed Observations.
    > >
    > >
    > > I'd be careful and make sure, if I were you. I don't think
    > > that the worm is stateless, as it wouldn't be able to spread
    > > if it just sent data over TCP without establishing the
    > > handshake first. When you just PSH without handshaking
    > > first, your data gets rejected.
    > >
    > > > -----Original Message-----
    > > > From: larosa, vjay [mailto:larosa_vjay@emc.com]
    > > > Sent: Thursday, March 13, 2003 11:32 AM
    > > > To: 'Rob Shein'; larosa, vjay; incidents@securityfocus.com
    > > > Subject: RE: CodeRed Observations.
    > > >
    > > >
    > > > There are no filters in place for viewing the firewall logs.
    > > > Even if there were, the attacks I am seeing are even targeted
    > > > to IP addresses that are not up and on-line in my network. So
    > > > how would a "get default.ida?XXX" string be sent to a host that
    > > > is,
    > > >
    > > > a) Not up on the network.
    > > > b) Behind a firewall that blocks ALL incoming port 80.
    > > >
    > > > If there is no three way handshake to set up a TCP session
    > > > I should not see this data trying to flow to my hosts (Dead
    > > > IP's or even live IP's). The traffic I am seeing is stateless
    > > > (Stick/Snot).
    > > >
    > > > vjl
    > > >
    > > > -----Original Message-----
    > > > From: Rob Shein [mailto:shoten@starpower.net]
    > > > Sent: Thursday, March 13, 2003 10:57 AM
    > > > To: 'larosa, vjay'; incidents@securityfocus.com
    > > > Subject: RE: CodeRed Observations.
    > > >
    > > >
    > > > Check your filters. You might be looking at traffic through
    > > > a selection filter that doesn't show the handshake, so that
    > > > you can concentrate on the content that passes back and
    > > > forth. That's what I usually find to be the case when
    > > > someone makes this kind of observation...
    > > >
    > > > > -----Original Message-----
    > > > > From: larosa, vjay [mailto:larosa_vjay@emc.com]
    > > > > Sent: Wednesday, March 12, 2003 7:48 PM
    > > > > To: 'incidents@securityfocus.com'
    > > > > Subject: FW: CodeRed Observations.
    > > > >
    > > > >
    > > > > > Hello,
    > > > > >
    > > > > > I have been watching this recent spike in CodeRed
    > > activity and one
    > > > > > thing I am noticing is the lack of TCP session
    > > > establishment. I am
    > > > > > seeing common get strings like this showing
    > > > > > up at my firewalls without ever establishing a TCP three
    > > > > way handshake. I
    > > > > > have seen several
    > > > > > hundred packets with in the last two days similar to this
    > > > > at my firewalls.
    > > > > >
    > > > > > 47 45 54 20 2F 64 65 66 61 75 6C 74 2E 69 64 61 GET
    > > > > /default.ida 3F
    > > > > > 58 58 58 58 58 58 58 58 58 58 58 58 58 58 58
    > > > > ?XXXXXXXXXXXXXXX 58 58
    > > > > > 58 58 58 58 58 58 58 58 58 58 58 58 58 58 XXXXXXXXXXXXXXXX
    > > > > 58 58 58
    > > > > > 58 58 58 58 58 58 58 58 58 58 58 58 58 XXXXXXXXXXXXXXXX 58
    > > > > 58 58 58
    > > > > > 58 58 58 58 58 58 58 58 58 58 58 58 XXXXXXXXXXXXXXXX
    > > > > >
    > > > >
    > > >
    > > Snip------------------------------------------------------------------
    > > > > > ----
    > > > > > ------------------------------------------------------
    > > > > >
    > > > > > I find it awfully strange that there is no handshake
    > > (not even a
    > > > > > single SYN to try and establish a session) but these
    > > > > packets show up
    > > > > > anyway. I also am not seeing an increase of port 80
    > > > > > scans in my firewall logs or with any of my IDS sensors. Is
    > > > > anybody else
    > > > > > out there seeing the
    > > > > > same things we are?
    > > > > >
    > > > > > Thanks!
    > > > > >
    > > > > > vjl
    > > > > >
    > > > > > V.Jay LaRosa EMC Corporation
    > > > > > Information Security 4400 Computer Dr.
    > > > > > (508)898-7433 office Westboro, MA 01580
    > > > > > (508)353-1348 cell www.emc.com
    > > > > > 888-799-9750 pager larosa_vjay@emc.com
    > > > > >
    > > > > >
    > > > > >
    > > > >
    > > > > --------------------------------------------------------------
    > > > > --------------
    > > > >
    > > > > <Pre>Lose another weekend managing your IDS?
    > > > > Take back your personal time.
    > > > > 15-day free trial of StillSecure Border Guard.</Pre>
    > > > > <A href="http://www.securityfocus.com/stillsecure">
    > > > > http://www.securityfocus.com/stillsecure </A>
    > > > >
    > > > >
    > > >
    > >
    >
    > ----------------------------------------------------------------------------
    >
    > <Pre>Lose another weekend managing your IDS?
    > Take back your personal time.
    > 15-day free trial of StillSecure Border Guard.</Pre>
    > http://www.securityfocus.com/stillsecure
    >

    -- 
    Kveðja,
    Tolli
    tolli@tol.li
    ----------------------------------------------------------------------------
    <Pre>Lose another weekend managing your IDS?
    Take back your personal time.
    15-day free trial of StillSecure Border Guard.</Pre>
    <A href="http://www.securityfocus.com/stillsecure"> http://www.securityfocus.com/stillsecure </A>
    

  • Next message: larosa, vjay: "RE: CodeRed Observations."

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