ppt - UCF CS

Scalability, Fidelity, and
Containment in the Potemkin
Virtual Honeyfarm
Michael Vrable, Justin Ma, Jay chen, David Moore, Erik
Vandekieft, Alex C. Snoeren, Geoffrey M. Voelker, Stefan
Savage
Collaborative Center for Internet Epidemiology and Defenses
Department of Computer Science and Engineering
Univsersty of California, San Diego
Background Info
Network Telescope Theory
HoneyPots – A system of Intrusion/Threat
Detection where the value lies in that all traffic in
system is not legitimate
High Interaction or Low Interaction?

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Benefit of Low Interaction is large number of IPs can
be covered
Benefit of High Interaction is you can gain better
insight into the methods used and possible outcomes
of attacks
Bottom Line
You can have one a system that
represents a larger net so you have better
odds of finding something malicious
Or, you can have a system that monitors a
smaller set of IPs because there is more
overhead in providing kernel and system
access to the potential threat, and not just
mimicking network presence.
Bottom Line ?
So why cant you have your cake and eat it too?
Is it possible to provide a system that will allow
you to combine the best of both worlds.
Can you provide a Honeyfarm solution that
allows you monitor a large IP set, and provide a
valid system for each threat to incubate so
analysis can be in-depth? Can you do it with out
throwing large amounts of money at it?
Basis of Paper
This is the aim of this paper.
Utilize VM technology and custom
software design to create a system which
has high fidelity, and can scale well to
monitor a large environment if the need
arises.
Don’t break the bank doing it either!
Problems
Resources


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Memory
CPU
HD Space
Routing


How do we route the packets so Honeyfarm is
invisible?
How do we route packets so as not to cause an
outbound attack?
Latency

How do we provide interaction so that the attacker
does not know he is in a virtual environment?
Solutions!
Flash Cloning

Allow Farm to scale as need arises
Delta Virtualization (Copy-On-Write)

Addresses timing and resource use of each
clone
Creative Routing

Limits farm to only dealing with IPs that solicit
communication.
Flash Cloning
VM Machine instantiation can have high
overhead and latency, especially when VM
needs to boot and load devices.
To work around this, provide a “Reference
Image”.
An Image of an already loaded O/S is kept
frozen and unchanged. When need arises
for a new VM, clone this one. It is already
to run, just change IPs.
Flash Cloning
Benefits



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Quicker Load time
New VMs can react to each new outside
probe/threat
Allows a pristine VM to be examined after
compromise. You have a baseline to compare
a compromised VM to.
Clone can be created and threat will only
receive initial delay between first packet and
response.
Flash Cloning
Courtesy of the paper and its authors
Delta Virtualization
Essentially an optimized Copy-on-Write
technique.
For each VM Cloned, the entire image
need not be copied.
There will always be static parts of the OS
memory that does not change.
If need for that specific VM to alter
memory tables arise, then copy memory
for that location and change memory table
for VM to point to new location
Delta Virtualization
Courtesy of the paper and its authors
Creative Routing
Each Incoming Packet is Mirrored at Edge
Router to HoneyFarm
The farm has it’s own machine dedicated
to routing packets.
For each packet destined for an IP known
to be unused, the gateway notifies Cloning
Manager on least busy machine to
allocate new clone with specific IP.
Creative Routing
After initial lag from cloning, clone is ready and
notifies Clone Manager.
Clone Manager tells gateway which then flushes
buffer of packets waiting for clone and adds
routing rule to push all future communication for
that IP address to that clone.
To prevent horizontal port scans from
overwhelming farm, all future unused attempts
from that IP are ignored to keep clone numbers
in check.
Here is where the creativity comes
in
What about threats that spread like worms?
Viruses that call home? Rootkits that update
themselves?
Each communication between an outside IP and
an Internal IP is considered a Universe and the
route reflects it.
If compromised clone attempts outside
communication, the communication is reflected
back toward another clone inside the farm.
Here is where the creativity comes
in
Thus, the farm can also serve as a ‘incubator’,
providing a microcosm for the threat to grow.
Also allows for the possibility of cross
contamination. You could setup rules to allow to
uniquely infected clones to communicate with
each other and create hybrid compromises.
Another unseen benefit is you can provide a
concrete spread rate of a new threat. Thus,
providing some reliable scale to rate new threats
on.
The numbers don’t lie
The largest HoneyFarm known to the
authors was Symantec’s DeepSight using
40 servers with VMware to mimic 2000 IP
addresses.
During Potemkin’s ‘Live Deployment’, the
max they were able to simulate was 2100
VMs using one gateway and 9 servers. All
using 2.8 GHZ Xeons’s with 2GB of
memory and a gigabit NIC. Roughly
$10,000 total by current market value.
Performance Numbers
Right hand side represents
possible future enhancements
by recycling data structures and
tables of VMs that were tore
down.
Tables Courtesy of the
Paper and it’s Authors.
Strengths
Provides some real good ideas to
maximize performance with limited
hardware.
Incubator idea is real interesting.
Infection rate idea is real interesting.
Considered legalities of HoneyFarm
infecting external IPs and also considered
Hybrid Infections.
Weaknesses
Live testing did not last longer then 10
minutes.
A lot of bugs still left to work out before the
solution could be considered stable
enough for long term deployment.
System can be exploited by attacker to
exhuast amount of resources in system.
Time characteristics can be used against
HoneyFarm to signal virtual environment.
Weaknesses
Threat could be able to look at limited devices
available and conclude in virtual environment.
Threat could also reference outside IP to
determine if in virtual environment.
Could only be useful in examining malicious
programs that are not designed to look for virtual
environments, as an actual attacker worth their
salt could determine it is virtual environment.
Extensions
Elaborate on the idea of incubation more.
Improve multiple OS support.
Enable packet analysis at gateway to
determine which OS to clone to provide
‘best fit’ for attack.
Stabilize system and introduce VM HD
support so each clone can get access to
swap space.