Stratosphere Project
Malware Detection in the Network. Behavioral Analysis with Machine Learning
García Sebastián PhD.
sebastian.garcia@agents.fel.cvut.cz
Live Slides
bit.ly
/stratos1
Stratosphere Project
https://stratosphereips.org/
Free
Software
Machine
Learning
Behavioral
IPS
Protecting
NGOs
Stratosphere Technical Pillars
Less is More
Disassociate
Verify
Analyze the behavior of
group of flows
.
Representation of
behaviour
from
detection
.
With
real
and
labeled
datasets and networks
Behaviors
Your behavior is usually the
same
when connecting with the same service.
Group flows going to a
specific service
by ignoring the source port. We have
our
connection
.
10.0.2.2-60.60.60.1-80-tcp
The connection, composed of several flows, now shows a
behavior
.
Using a service, you go from one
state
to the next state.
Each
flow
has its own state.
We model the states using four features.
Size
of the flow.
Duration
of the flow.
Periodicity
of the flow.
Time
between flows.
From Connections to States
States as Letters
The Behavior of a Connection
10.0.2.111-217.23.10.139-80-tcp 55*V0v00v*E*v*v*v*v*E*v
1 flow -> 4 features -> 1 letter + 1 symbol
Stratosphere Behavior Demo
Stratosphere Testing Framework: Create and Analyze Behaviors
https://mcfp.felk.cvut.cz/publicDatasets/CTU-Malware-Capture-Botnet-112-1/
About the Behaviors
Malware mostly generate the
same
behavior.
Changing the behavior is
costly
for the attacker.
These behaviors do
not expire
quickly.
Infections go unnoticed for
hours
. There is time.
From the letters create a Markov Chains behavioral model
Detection with Markov Chains
Train Markov Models with known Behaviors: Malware and Normal.
Detection with Markov Chains
Compare the unknown traffic of a network to each trained Markov Model.
Trained M1
Unknown Connection
87,a,a,b,B,i*i*i*i*i (?)
Trained M2
Trained M3
Stratosphere Detection Demo
Stratosphere Testing Framework
Stratosphere Linux IPS
Results
How to measure?
Packets/Flows/Connections/IPs?
Per minute? Per hour? Per day?
Who is putting the labels?
In Stratosphere it also depends on the models used.
Stratosphere Malware and Normal Dataset
https://stratosphereips.org/category/dataset.html
Results
In our datasets
96% TPR. Our own botnet traffic connections that are detected.
Real Traffic
~0.0002% FPR (30 FP in 132,000 connections/5min)
Novel Success cases: Linux Botnet, DDoS, etc.
Errors? For sure.
Stratosphere Data Analysis
Cloud-based
Detection service for NGOs.
Add
new
algorithms continually.
Update
the models.
Verify
the detections if necessary.
NGOs can send the Flows or
only the letters! Privacy
matters.
Thanks!
Sebastian Garcia
sebastian.garcia@agents.fel.cvut.cz
@stratosphereips
https://stratosphereips.org