Re: No Security is Bad Security:

From: Jan B. Koum (jkbat_private)
Date: Wed Feb 03 1999 - 08:33:10 PST

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    [aleph: feel free to pick out certain points and cut others out]
    
    On Wed, Feb 03, 1999 at 01:50:20AM -0600, Kevin Day <toastyat_private> wrote:
    > >
    > > Mistakes Made in Incidence Response:
    > > -----------------------------------
    > >
    > > 1) Don't log in as root on a machine that most likely has been
    > > compromised. Bsd things can happen.
    > >
    > > 2) Don't go around blithely executing binaries. (I feel rather stupid
    > > about that)
    > >
    > > 3) Do *immediately* take the machine offline, and mount the disks on
    > > another system for analysis.
    >
    >
    > If mounting on another system, and your OS supports it, mount with the
    > 'noexec' option, to make sure you don't accidently infect another system, as
    > well as the rdonly flag to make sure you don't damage evidence. You may also
    > want to consider 'noatime', to keep things really pristine, if you don't go
    > 'ro'.
    >
    >              noexec  Do not allow execution of any binaries on the mounted
    >                      file system.  This option is useful for a server that has
    >                      file systems containing binaries for architectures other
    >                      than its own.
    >
    >
    >
    > Kevin
    
    	I would like to bring up another big point the author of the original
    	email forgot: wardialing. No matter how much you port scan, you will
    	find something that surprises you when you wardial. Honest.
    
    	Ok.. there is more then one point in this eMail:
    
    > 1) Don't log in as root on a machine that most likely has been
    > compromised. Bsd things can happen.
    
            You have to login as root to shutdown the system. You don't
            want to 'just turn it off' since you can loose data.
    
    > 3) Do *immediately* take the machine offline, and mount the disks on
    > another system for analysis.
    
            True. Dont' forget to mount rdonly,noexec,nosuid,nodev
    	(mentioned about and some flags are redundant).
    
    > 1) we have no firewall nor tcpd running, so there is no effective access
    > control or access logging. We have incredibly primitive router filtering,
    > which eliminates only the most basic of IP-spoofing attacks.
    
    	You can install ipf if you are on solaris. Or get a FreeBSD with
    	two nics and use that as your firewall.
    
    > 6) we did not purchase or implement any Intrusion Detection Software.
    > [IDS]
    
    	http://www.l0pht.com/NFR
    	http://www.nfr.com
    
    >
    > Not using tripwire cost us a lot, in that a) we had to rebuild every last
    > GNU program from source, and b) we did not have it available as a means of
    > detecting 'wrongness' on a production system.
    
    	Take a look at how FreeBSD/NetBSD/OpenBSD makes a use of CVS/CVSup
    	to bring you things like 'make world' or 'make build'.. will make
    	rebuild from source very easy. No GNU though. Well.. I'll stop here.
    
    -- Yan
    
    I don't have the password .... + Jan Koum
    But the path is chainlinked .. | Spelled Jan, pronounced Yan. There.
    So if you've got the time .... | Web: http://www.best.com/~jkb
    Set the tone to sync ......... + OS: http://www.FreeBSD.org
    



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