Threat Hunting

© 2017 SPLUNK INC.© 2017 SPLUNK INC.
Threat Hunting With Splunk
Lee Imrey | Splunk Security Specialist
August 16, 2017 | Cincinnati, OH

© 2017 SPLUNK INC.
▶ Threat Hunting Basics
▶ Threat Hunting Data Sources
▶ Know Your Endpoint
▶ Cyber Kill Chain
▶ Walkthrough of Attack Scenario Using Core Splunk (hands on)
▶ Advanced Threat Hunting Techniques & Tools
▶ Enterprise Security Walkthrough
▶ Applying Machine Learning and Data Science to Security
Agenda

© 2017 SPLUNK INC.
Hands On? This Won’t Work.

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Some familiarity with…
▶ CSIRT/SOC Operations
▶ General understanding of Threat Intelligence
▶ General understanding of DNS, Proxy, and
Endpoint types of data
Am I in the right place?

© 2017 SPLUNK INC.
What is Threat Hunting, Why do You Need it?
1 The Who, What, Where, When, Why and How of Effective Threat Hunting, SANS Feb 2016
2 Cyber Threat Hunting - Samuel Alonso blog, Jan 2016
“Threat Hunting is not new, it’s
just evolving!”
Threat hunting - the act of
aggressively intercepting,
tracking and eliminating cyber
adversaries as early as possible
in the Cyber Kill Chain2
What?
Threats are human. Focused and
funded adversaries will not be
countered by security boxes on
the network alone. Threat
hunters are actively searching for
threats to prevent or minimize
damage [before it happens] 1
Why?

© 2017 SPLUNK INC.
Locard’s Exchange Principle

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VS

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Human Threat Hunter
Objectives > Hypotheses > Expertise
Key Building Blocks to Drive Threat Hunting
Maturity
Ref: The Who, What, Where, When, Why and How
of Effective Threat Hunting, SANS Feb 2016
Search &
Visualisation
Enrichment
Data
Automation

© 2017 SPLUNK INC.
Henry A. Crumpton
The Art of Intelligence: Lessons From a Life in the CIA’s Clandestine Service
““A good intelligence officer cultivates an
awareness of what he or she does not
know. You need a dose of modesty to
acknowledge your own ignorance - even
more, to seek out your ignorance.”

© 2017 SPLUNK INC.
SANS Threat Hunting Maturity
Ad Hoc
Search
Statistical
Analysis
Visualization
Techniques
Aggregation Machine Learning/
Data Science
85% 55% 50% 48% 32%
Source: SANS IR & Threat Hunting Summit 2016

© 2017 SPLUNK INC.
Hypotheses
Automated
Analytics
Data Science
& Machine
Learning
Data &
Intelligence
Enrichment
Data Search
Visualisation
Maturity
How Splunk Helps You Drive Threat Hunting Maturity
Human
Threat
Hunter
Threat Hunting Automation
Integrated & out of the box automation tooling from artifact query,
contextual “swim-lane analysis”, anomaly & time series analysis
to advanced data science leveraging machine learning
Threat Hunting Data Enrichment
Enrich data with context and threat-intel across the stack or time
to discern deeper patterns or relationships
Search & Visualise Relationships for Faster Hunting
Search and correlate data while visually fusing results for faster
context, analysis and insight
Ingest & Onboard Any Threat Hunting Machine Data Source
Enable fast ingestion of any machine data through efficient
indexing, a big data real time architecture and ‘schema on the
read’ technology
Search &
Visualisation
Enrichment
Data
Automation

© 2017 SPLUNK INC.
▶ IP Addresses: threat intelligence, blacklist, whitelist, reputation monitoring
Tools: Firewalls, Proxies, Splunk Stream, Bro, IDS
▶ Network Artifacts and Patterns: network flow, packet capture, active network connections, historic
network connections, ports and services
Tools: Splunk Stream, Bro IDS, FPC, Netflow
▶ DNS: activity, queries and responses, zone transfer activity
Tools: Splunk Stream, Bro IDS, OpenDNS
▶ Endpoint – Host Artifacts and Patterns: users, processes, services, drivers, files, registry, hardware,
memory, disk activity, file monitoring: hash values, integrity checking and alerts, creation or deletion
Tools: Windows/Linux, Carbon Black, Tanium, Tripwire, Active Directory
▶ Vulnerability Management Data
Tools: Tripwire IP360, Qualys, Nessus
▶ User Behavior Analytics: TTPs, user monitoring, time of day location, HR watchlist
Splunk UBA, (All of the above)
Hunting Tools: Internal Data

© 2017 SPLUNK INC.
Typical Data Sources
Attacker, know relay/C2 sites, infected sites, IOC,
attack/campaign intent and attribution
Where they went, who talked to whom, attack
transmitted, abnormal traffic, malware download
What process is running (malicious, abnormal, etc.)
Process owner, registry mods, attack/malware artifacts,
patching level, attack susceptibility
Access level, privileged users, likelihood of infection,
where they might be in kill chain
Threat
intelligence
Network
Endpoint
Access/Identity
• Third-party threat intel
• Open-source blacklist
• Internal threat intelligence
• Endpoint (AV/IPS/FW)
• Malware detection
• PCLM
• DHCP
• OS logs
• Patching
• Active Directory
• LDAP
• CMDB
• Operating system
• Database
• VPN, AAA, SSO
• Firewall, IDS, IPS
• DNS
• Email
• Web proxy
• NetFlow
• Network

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Threat Intelligence
Network
Security Intelligence

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▶ TA Available on the App Store
▶ Great blog post to get you started
▶ Increases the fidelity of Microsoft Logging
Know Your Endpoint:
Microsoft Sysmon Primer
Blog Post:
http://blogs.splunk.com/2014/11/24/monitoring-network-traffic-with-sysmon-and-splunk/

© 2017 SPLUNK INC.
Log In Credentials
January & February https://od-threat-hunting-wrksp-portland-01.splunkoxygen.com
March & April https://od-threat-hunting-wrksp-portland-02.splunkoxygen.com
May & June https://od-threat-hunting-wrksp-portland-03.splunkoxygen.com
July & August https://od-threat-hunting-wrksp-portland-04.splunkoxygen.com
September & October https://od-threat-hunting-wrksp-portland-05.splunkoxygen.com
November & December https://od-threat-hunting-wrksp-portland-06.splunkoxygen.com
User: hunter
Password: pr3dat0r
Birth Month

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Sysmon Event Tags: Optional Search
Maps Network Comm to process_id
Process_id creation and mapping to parentprocess_id

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sourcetype=X* | search tag=communicate

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sourcetype=X* | dedup tag| search tag=process

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Data Source Mapping
Web Email Endpoint Proxy/DNS
CMDB and Threat Intelligence
Recon Weaponize Deliver Exploit Install
Command
&
Control
Action

© 2017 SPLUNK INC.
Web Email Endpoint Proxy/DNS
CMDB and Threat Intelligence
Recon Weaponize Deliver Exploit Install
Command
&
Control
Action
Demo Story - Kill Chain Framework
Successful brute force
– download sensitive
pdf document
Weaponize the pdf file with
Zeus Malware
Convincing email
sent with
weaponized pdf
Vulnerable pdf reader exploited
by malware. Dropper created
on machinea
Dropper retrieves
and installs the
malware
Persistence via regular
outbound comm
Data exfiltration

© 2017 SPLUNK INC.
Servers
Storage
DesktopsEmail Web
Transaction
Records
Network
Flows
DHCP/ DNS
Hypervisor Custom Apps
Physical
Access
Badges
Threat Intelligence
Mobile
CMDB
Stream Investigations – Choose Your Data Wisely
Intrusion
Detection
Firewall
Data Loss
Prevention
Anti-Malware
Vulnerability
Scans
Traditional
Authentication

© 2017 SPLUNK INC.
APT Transaction Flow Across Data Sources
.pdf executes & unpacks malware
overwriting and running “allowed” programs
Threat
Intelligence
Auth - User Roles
Host
Activity/Security
Network
Activity/Security
Transaction
Gain Access
to System
Create Additional
Environment
Conduct
Business
Svchost.exeCalc.exe
Attacker hacks website.
Steals .pdf files
Web Portal
Attacker
creates malware,
embed in .pdf
Read email, open attachment
Emails
to the target EMAIL
HTTP (web) session to
command & control server
Remote control,
Steal data,
Persist in company,
Rent as botnet
WEB
Our Investigation begins by detecting high risk
communications through the proxy, at the
endpoint, and even a DNS call.

© 2017 SPLUNK INC.
index=zeus_demo3
in search:

© 2017 SPLUNK INC.
To begin our investigation,
we will start with a quick
search to familiarize
ourselves with the data
sources.
In this demo environment,
we have a variety of
security relevant data
including…
Web
DNS
Proxy
Firewall
Endpoint
Email

© 2017 SPLUNK INC.
Take a look at the
endpoint data source. We
are using the Microsoft
Sysmon TA.
We have endpoint visibility
into all network
communication and can
map each connection
back to a process.
}
We also have detailed info
on each process and can
map it back to the user
and parent process.
}
Lets get our day started by looking
using threat intel to prioritize our efforts
and focus on communication with
known high risk entities.

© 2017 SPLUNK INC.
We have multiple source
IPs communicating to high
risk entities identified by
these 2 threat sources.
We are seeing high risk
communication from
multiple data sources.
We see multiple threat intel related
events across multiple source types
associated with the IP Address of Chris
Gilbert. Let’s take closer look at the IP
Address.
We can now see the owner of the system
(Chris Gilbert) and that it isn’t a PII or PCI
related asset, so there are no immediate
business implications that would require
informing agencies or external customers
within a certain timeframe.
This dashboard is based on event
data that contains a threat intel
based indicator match( IP Address,
domain, etc.). The data is further
enriched with CMDB based
Asset/identity information.

© 2017 SPLUNK INC.
We are now looking at only threat
intel related activity for the IP
Address associated with Chris
Gilbert and see activity spanning
endpoint, proxy, and DNS data
sources.
These trend lines tell a very
interesting visual story. It appears
that the asset makes a DNS query
involving a threat intel related domain
or IP Address.
ScrollDown
Scroll down the dashboard to examine
these threat intel events associated
with the IP Address.
We then see threat intel related
endpoint and proxy events occurring
periodically and likely communicating
with a known Zeus botnet based on
the threat intel source (zeus_c2s).

© 2017 SPLUNK INC.
It’s worth mentioning that at this point you
could create a ticket to have someone re-
image the machine to prevent further
damage as we continue our investigation
within Splunk.
Within the same dashboard, we have
access to very high fidelity endpoint data
that allows an analyst to continue the
investigation in a very efficient manner. It
is important to note that near real-time
access to this type of endpoint data is not
not common within the traditional SOC.
The initial goal of the investigation is to
determine whether this communication
is malicious or a potential false
positive. Expand the endpoint event to
continue the investigation.
Proxy related threat intel matches are
important for helping us to prioritize our
efforts toward initiating an investigation.
Further investigation into the endpoint is
often very time consuming and often
involves multiple internal hand-offs to other
teams or needing to access additional
systems.
This encrypted proxy traffic is concerning
because of the large amount of data
(~1.5MB) being transferred which is
common when data is being exfiltrated.

© 2017 SPLUNK INC.
Exfiltration of data is a serious concern
and outbound communication to
external entity that has a known threat
intel indicator, especially when it is
encrypted as in this case.
Lets continue the investigation.
Another clue. We also see that
svchost.exe should be located in a
Windows system directory but this is
being run in the user space. Not good.
We immediately see the outbound
communication with 115.29.46.99 via https
is associated with the svchost.exe
process on the windows endpoint. The
process id is 4768. There is a great deal
more information from the endpoint as you
scroll down such as the user ID that
started the process and the associated
CMDB enrichment information.

© 2017 SPLUNK INC.
We have a workflow action that will link
us to a Process Explorer dashboard
and populate it with the process id
extracted from the event (4768).

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This is a standard Windows app, but
not in its usual directory, telling us that
the malware has again spoofed a
common file name.
We also can see that the parent
process that created this
suspicuous svchost.exe process is
called calc.exe.
This has brought us to the Process
Explorer dashboard which lets us view
Windows Sysmon endpoint data.
Suspected Malware
Lets continue the investigation by
examining the parent process as this
is almost certainly a genuine threat
and we are now working toward a root
cause.
This is very consistent with Zeus
behavior. The initial exploitation
generally creates a downloader or
dropper that will then download the
Zeus malware. It seems like calc.exe
may be that downloader/dropper.
Suspected Downloader/Dropper
This process calls itself “svchost.exe,” a
common Windows process, but the
path is not the normal path for
svchost.exe.
…which is a common trait of malware
attempting to evade detection. We also
see it making a DNS query (port 53)
then communicating via port 443.

© 2017 SPLUNK INC.
The Parent Process of our suspected
downloader/dropper is the legitimate PDF
Reader program. This will likely turn out to
be the vulnerable app that was exploited in
this attack.
Suspected Downloader/Dropper
Suspected Vulnerable AppWe have very quickly moved from
threat intel related network and
endpoint activity to the likely
exploitation of a vulnerable app. Click
on the parent process to keep
investigating.

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We can see that the PDF
Reader process has no
identified parent and is the
root of the infection.
ScrollDown
activity related to the PDF reader
process.

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Chris opened 2nd_qtr_2014_report.pdf
which was an attachment to an email!
We have our root cause! Chris opened a weaponized
.pdf file which contained the Zeus malware. It
appears to have been delivered via email and we
have access to our email logs as one of our important
data sources. Lets copy the filename
2nd_qtr_2014_report.pdf and search a bit further to
determine the scope of this compromise.

© 2017 SPLUNK INC.
Lets dig a little further into 2nd_qtr_2014_report.pdf to
determine the scope of this compromise.

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index=zeus_demo3 2nd_qtr_2014_report.pdf
in search:

© 2017 SPLUNK INC.
Lets search though multiple data sources to
quickly get a sense for who else may have
have been exposed to this file.
We will come back to the web activity
that contains reference to the pdf file
but lets first look at the email event to
determine the scope of this apparent
phishing attack.

© 2017 SPLUNK INC.
We have access to the email body
and can see why this was such a
convincing attack. The sender
apparently had access to
sensitive insider knowledge and
hinted at quarterly results.
There is our attachment.
Hold On! That’s not our Domain
Name! The spelling is close but
it’s missing a “t”. The attacker
likely registered a domain name
that is very close to the company
domain hoping Chris would not
notice.
This looks to be a very
targeted spear phishing
attack as it was sent to only
one employee (Chris).

© 2017 SPLUNK INC.
Root Cause Recap
Threat
Intelligence
Endpoint
Host
Activity/Security
Network
Activity/Security
Transaction
Gain Access
to System
Create Additional
Environment
Conduct
Business
Svchost.exeCalc.exe
Steals .pdf files
Web Portal
Attacker
creates malware,
embed in .pdf
Emails
to the target EMAIL
Remote control,
Steal data,
Persist in company,
Rent as botnet
WEB
We utilized threat intel to detect
communication with known high risk indicators
and kick off our investigation then worked
backward through the kill chain toward a root
cause.
Key to this investigative process is the ability
to associate network communications with
endpoint process data.
This high value and very relevant ability to
work a malware related investigation through
to root cause translates into a very streamlined
investigative process compared to the legacy
SIEM based approach.

© 2017 SPLUNK INC.
Lets revisit the search for additional information
on the 2nd_qtr_2014-_report.pdf file.
We understand that the file was delivered via
email and opened at the endpoint. Why do we
see a reference to the file in the
access_combined (web server) logs?
Click
Select the access_combined
sourcetype to investigate further.

© 2017 SPLUNK INC.
The results show 54.211.114.134 has
accessed this file from the web portal of
buttergames.com.
There is also a known threat intel
association with the source IP
Address downloading (HTTP GET)
the file.

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Select the IP Address, left-click, then
select “New search”. We would like to
understand what else this IP Address has
accessed in the environment.

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That’s an abnormally large
number of requests sourced
from a single IP Address in a
~90 minute window.
This looks like a scripted
action given the constant high
rate of requests over the
below window.
ScrollDown
other interesting fields to further
investigate.
Notice the Googlebot
useragent string which is
another attempt to avoid
raising attention..

© 2017 SPLUNK INC.
The requests from 52.211.114.134 are
dominated by requests to the login page
(wp-login.php). It’s clearly not possible to
attempt a login this many times in a short
period of time – this is clearly a scripted
brute force attack.
After successfully gaining access to our
website, the attacker downloaded the pdf
file, weaponized it with the zeus malware,
then delivered it to Chris Gilbert as a
phishing email.
The attacker is also accessing admin pages
which may be an attempt to establish
persistence via a backdoor into the web
site.

© 2017 SPLUNK INC.
Threat
Intelligence
Endpoint
Host
Activity/Security
Network
Activity/Security
Transaction
Gain Access
to System
Create Additional
Environment
Conduct
Business
Svchost.exeCalc.exe
Steals .pdf files
Web Portal
Attacker
creates malware,
embed in .pdf
Emails
to the target EMAIL
Remote control,
Steal data,
Persist in company,
Rent as botnet
WEB
We continued the investigation
by pivoting into the endpoint data
source and used a workflow
action to determine which
process on the endpoint was
responsible for the outbound
communication.
We began by reviewing threat
intel related events for a
particular IP address and
observed DNS, Proxy, and
Endpoint events for a user in
Sales.
Investigation complete! Lets get this
turned over to Incident Reponse team.
We traced the svchost.exe
Zeus malware back to it’s
parent process ID which was
the calc.exe
downloader/dropper.
Once our root cause analysis was
complete, we shifted out focus into
the web logs to determine that the
sensitive pdf file was obtained via
a brute force attack against the
company website.
We were able to see which file
was opened by the vulnerable
app and determined that the
malicious file was delivered to
the user via email.
A quick search into the mail
logs revealed the details
behind the phishing attack and
revealed that the scope of the
compromise was limited to just
the one user.
We traced calc.exe back to the
vulnerable application PDF
Reader.
Kill Chain Analysis Across Data Sources

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BREAK
10 MINUTES

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BONUS!
- SQLi
- DNS Exfilatration
- Splunk Security Essentials

© 2017 SPLUNK INC.
▶ SQL injection
▶ Code injection
▶ OS commanding
▶ LDAP injection
▶ XML injection
▶ XPath injection
▶ SSI injection
▶ IMAP/SMTP injection
▶ Buffer overflow
SQL Injection

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Imperva Web Attacks Report, 2015

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The Anatomy of an SQL Injection Attack
SELECT * FROM users WHERE email='xxx@xxx.com'
OR 1 = 1 -- ' AND password='xxx';
xxx@xxx.xxx' OR 1 = 1 -- '
xxx
admin@admin.sys
1234
An attacker might supply:

© 2017 SPLUNK INC.
…and so far this year… 39

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index=web_vuln password select

© 2017 SPLUNK INC.
Our learning environment consists of:
▶ A bunch of publically-accessible
single Splunk servers
▶ Each with ~5.5M events, from real
environments but massaged:
• Windows Security events
• Apache web access logs
• Bro DNS & HTTP
• Palo Alto traffic logs
• Some other various bits
What have we here?

© 2017 SPLUNK INC.
https://splunkbase.splunk.com/app/1528/
Search for possible SQL injection in your events:
• looks for patterns in URI query field to see if anyone has
injected them with SQL statements
• use standard deviations that are 2.5 times greater than
the average length of your URI query field
▶ Macros used
• sqlinjection_pattern(sourcetype, uri query field)
• sqlinjection_stats(sourcetype, uri query field)

© 2017 SPLUNK INC.
Regular Expression FTW
sqlinjection_rex is a search macro. It contains:
(?<injection>(?i)select.*?from|union.*?select|'$|delete.*?from|update.*?set|alter.*?table|([%27|'](%2
0)*=(%20)*[%27|'])|w*[%27|']or)
Which means: In the string we are given, look for ANY of the following matches and put that into the
“injection” field.
• Anything containing SELECT followed by FROM
• Anything containing UNION followed by SELECT
• Anything with a ‘ at the end
• Anything containing DELETE followed by FROM
• Anything containing UPDATE followed by SET
• Anything containing ALTER followed by TABLE
• A %27 OR a ‘ and then a %20 and any amount of characters then a %20 and then a %27 OR a ‘
• Note: %27 is encoded “’” and %20 is encoded <space>
• Any amount of word characters followed by a %27 OR a ‘ and then “or”

© 2017 SPLUNK INC.
Bonus: Try out the SQL Injection app!

© 2017 SPLUNK INC.
▶ SQL injection provide attackers with easy access to data
▶ Detecting advanced SQL injection is hard – use an app!
▶ Understand where SQLi is happening on your network and put a stop to it.
▶ Augment your WAF with enterprise-wide Splunk searches.
Summary: Web Attacks/SQL Injection

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DNS Exfiltration

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domain=corp;user=dave;password=12345
DNS Query:
ZG9tYWluPWNvcnA7dXNlcj1kYXZlO3Bhc3N3b3JkPTEyM
zQ1DQoNCg==.attack.com
ZG9tYWluPWNvcnA7dXNlcj1kYXZlO3Bhc3N3b3JkPTEyMzQ1DQoNCg==
DNS Exfiltration
Firewall

© 2017 SPLUNK INC.
DNS exfil tends to be overlooked within an ocean of DNS data.
Let’s fix that!
DNS Exfiltration

© 2017 SPLUNK INC.
But the big difference is the way how stolen data is exfiltrated:
the malware used DNS requests!
https://blog.gdatasoftware.com/2014/10/23942-new-
frameworkpos-variant-exfiltrates-data-via-dns-requests
“
”
… few organizations actually keep detailed logs or records of the DNS
traffic traversing their networks — making it an ideal way to siphon data
from a hacked network.
http://krebsonsecurity.com/2015/05/deconstructing-the-2014-sally-beauty-
breach/#more-30872
“
”
▶ FrameworkPOS: a card-stealing program that exfiltrates data from the target’s
network by transmitting it as domain name system (DNS) traffic
DNS Exfiltration

© 2017 SPLUNK INC.
DNS exfil detection – tricks of the trade
 parse URLs & complicated TLDs (Top Level Domain)
 calculate Shannon Entropy
List of provided lookups
• ut_parse_simple(url)
• ut_parse(url, list) or ut_parse_extended(url, list)
• ut_shannon(word)
• ut_countset(word, set)
• ut_suites(word, sets)
• ut_meaning(word)
• ut_bayesian(word)
• ut_levenshtein(word1, word2)

© 2017 SPLUNK INC.
Layman’s definition: a score reflecting the randomness or
measure of uncertainty of a string
▶ Examples
• The domain aaaaa.com has a Shannon Entropy score of 1.8 (very low)
• The domain google.com has a Shannon Entropy score of 2.6 (rather low)
• A00wlkj—(-a.aslkn-C.a.2.sk.esasdfasf1111)-890209uC.4.com has a Shannon
Entropy score of 3 (rather high)
Shannon Entropy

© 2017 SPLUNK INC.
index=bro sourcetype=bro_dns
| `ut_parse(query)`
| `ut_shannon(ut_subdomain)`
| eval sublen =
length(ut_subdomain)
| table ut_domain ut_subdomain
ut_shannon sublen
▶ TIPS
• Leverage our Bro DNS data
• Calculate Shannon Entropy scores
• Calculate subdomain length
• Display details
Detecting Data Exfiltration

© 2017 SPLUNK INC.
▶ TIPS
• Leverage our Bro DNS data
• Calculate Shannon Entropy scores
• Calculate subdomain length
• Display count, scores, lengths, deviations
… | stats
count
avg(ut_shannon) as avg_sha
avg(sublen) as avg_sublen
stdev(sublen) as stdev_sublen
by ut_domain
| search avg_sha>3
avg_sublen>20 stdev_sublen<2

© 2017 SPLUNK INC.
▶ RESULTS
• Exfiltrating data requires many DNS requests – look for high counts
• DNS exfiltration to mooo.com and chickenkiller.com

© 2017 SPLUNK INC.
▶ Exfiltration by DNS and ICMP is a very common technique
▶ Many organizations do not analyze DNS activity – do not be like them!
▶ No DNS logs? No Splunk Stream? Look at FW byte counts
Summary: DNS exfiltration

© 2017 SPLUNK INC.
Splunk Security Essentials

© 2017 SPLUNK INC.
Security Essentials: Free as in Beer

© 2017 SPLUNK INC.
Identify bad guys in your environment:
 45+ use cases common in UEBA products, all free on
Splunk Enterprise
 Target external attackers and insider threat
 Scales from small to massive companies
 Save from the app, send results to ES/UBA
You can solve use cases today for free, then
use Splunk UBA for advanced ML detection.

© 2017 SPLUNK INC.
▶ First Time Seen
Powered by Stats
▶ Time Series
Analysis With
Standard Deviation
▶ General Security
Analytics Searches
Types of Use Cases

© 2017 SPLUNK INC.
Data Sources
Electronic Medical Records
Source Code Repository
Firewall
EmailLogs

© 2017 SPLUNK INC.
How does the app work? How does the app scale?
▶ Leverages primarily | stats for UEBA
▶ Also implements several advanced
Splunk searches (URL Toolbox, etc.)
▶ App automates the utilization of high
scale techniques
▶ Summary indexing for Time Series,
caching in lookup for First Time

© 2017 SPLUNK INC.
Splunk Enterprise
Security

© 2017 SPLUNK INC.
Hypotheses
Automated
Analytics
Data Science &
Machine
Learning
Data &
Intelligence
Enrichment
Data Search
Visualisation
Maturity
78
Splunk Enterprise
- Big Data Analytics Platform -
Splunk Enterprise
Security
- Security Analytics Platform -
Threat Hunting Data
Enrichment
Threat Hunting
Automation
Ingest & Onboard Any
Threat Hunting Machine
Data Source
Search & Visualise
Relationships for Faster
Hunting
User Behavior
Analytics
- Security Data Science Platform -
Search &
Visualization
Enrichment
Data
Automation

© 2017 SPLUNK INC.
Other Items To Note
Items to Note
Navigation - How to Get Here
Description of what to click on
Click

© 2017 SPLUNK INC.
Key Security Indicators (build your own!)
Sparklines
Editable

© 2017 SPLUNK INC.
Various ways to filter data
Malware-Specific KSIs and Reports
Most Popular Signatures Across All
Technologies
Security Domains -> Endpoint -> Malware Center

© 2017 SPLUNK INC.
Filterable
KSIs specific to Risk
Risk assigned to system,
user or other
Under Advanced Threat, select Risk Analysis

© 2017 SPLUNK INC.
(Scroll Down)
Recent Risk Activity
Under Advanced Threat, Select Risk Analysis

© 2017 SPLUNK INC.
Filterable, down to IoC
KSIs specific to Threat
Most active threat source
Scroll down…
Scroll
Under Advanced Threat, Select Threat Activity

© 2017 SPLUNK INC.
Specifics about recent threat matches
Under Advanced Threat, Select Threat Activity

© 2017 SPLUNK INC.
Artifact Categories –
click different tabs…
STIX feed
Custom feed
Under Advanced Threat, Select Threat Artifacts

© 2017 SPLUNK INC.
Data from asset framework
Configurable Swimlanes
Darker=more events
All happened around same timeChange to “Today”
if needed
Asset Investigator, enter “192.168.56.102”

© 2017 SPLUNK INC.
Computer
Science
Statistics
and Math
Machine
Learning
Security
Engineer
Security
Analyst
Cyber Security
Expertise
Security Data Science

© 2017 SPLUNK INC.
Supervised Machine Learning: Focus is to build models
that make predictions based on evidence (labeled data) in
the presence of uncertainty. As adaptive algorithms
identify patterns in data, it "learns" from the observations.
Unsupervised Machine Learning: Used to draw
inferences from datasets consisting of input data without
labeled responses.
Semi-Supervised Machine Learning
Types of Machine Learning

© 2017 SPLUNK INC.
▶ Regression: A regression problem is when the output variable is a real value,
such as “authorizations over time”.
▶ Classification: A classification problem is when the output variable is a category,
such as “malicious” or “non-malicious.” or “authorized” and “not authorized”.
▶ Anomaly Detection: Identify unusual activity, learn what normal looks like.
Example: A history of normal web authorizations to then identify anything
significantly different.
Supervised Machine Learning

© 2017 SPLUNK INC.
▶ Regression is used for predictive modeling to investigate the relationship
between a dependent (target) and independent variables (predictors).
▶ Examples of regression algorithms:
• Linear Regression
• Logistic Regression
• Stepwise Regression
• Multivariate Adaptive Regression Splines (MARS)
• Locally Estimated Scatterplot Smoothing (LOESS)
• Ordinary Least Squares Regression (OLSR)
Supervised Machine Learning Regression

© 2017 SPLUNK INC.
Supervised Machine Learning
Domain Name TotalCnt RiskFactor AGD SessionTime RefEntropy NullUa Outcome
yyfaimjmocdu.com 144 6.05 1 1 0 0 Malicious
jjeyd2u37an30.com 6192 5.05 0 1 0 0 Malicious
cdn4s.steelhousemedia.com 107 3 0 0 0 0 Benign
log.tagcade.com 111 2 0 1 0 0 Benign
go.vidprocess.com 170 2 0 0 0 0 Benign
statse.webtrendslive.com 310 2 0 1 0 0 Benign
cdn4s.steelhousemedia.com 107 1 0 0 0 0 Benign
log.tagcade.com 111 1 0 1 0 0 Benign

© 2017 SPLUNK INC.
Test
Raw
Security Data
Production
Supervised Machine Learning Process
Algorithm
Product
Sample Pre/Train/Model
Verification

© 2017 SPLUNK INC.
▶ No tuning
▶ Programmatically finds trends
Unsupervised Machine Learning
Raw Security Data Automated Clustering
▶ UBA is primarily unsupervised
▶ Rigorously tested for fit
Algorithm

© 2017 SPLUNK INC.
▶ Splunk Supported framework for building ML Apps
• Get it for free: http://tiny.cc/splunkmlapp
▶ Leverages Python for Scientific Computing (PSC) add-on:
• Open-source Python data science ecosystem
• NumPy, SciPy, scitkit-learn, pandas, statsmodels
▶ Showcase use cases: Predict Hard Drive Failure, Server Power Consumption,
Application Usage, Customer Churn & more
▶ Standard algorithms out of the box:
• Supervised: Logistic Regression, SVM, Linear Regression, Random Forest, etc.
• Unsupervised: KMeans, DBSCAN, Spectral Clustering, PCA, KernelPCA, etc.
▶ Implement one of 300+ algorithms by editing Python scripts
ML Toolkit & Showcase
ML Toolkit and
Showcase

© 2017 SPLUNK INC.
Hypotheses
Automated
Analytics
Data Science &
Machine
Learning
Data &
Intelligence
Enrichment
Data Search
Visualisation
Maturity
112
Splunk Enterprise
- Big Data Analytics Platform -
Splunk Enterprise
Security
- Security Analytics Platform -
Threat Hunting Data
Enrichment
Threat Hunting
Automation
Ingest & Onboard Any
Threat Hunting Machine
Data Source
Search & Visualise
Relationships for Faster
Hunting
User Behavior
Analytics
- Security Data Science Platform -
Search &
Visualization
Enrichment
Data
Automation

© 2017 SPLUNK INC.
Machine Learning Security Use Cases
113
MachineLearningUseCases
Polymorphic Attack Analysis
Behavioral Peer Group Analysis
User & Entity Behavior Baseline
Entropy/Rare Event Detection
Cyber Attack / External Threat Detection
Reconnaissance, Botnet and C&C Analysis
Lateral Movement Analysis
Statistical Analysis
Data Exfiltration Models
IP Reputation Analysis
Insider Threat Detection
User/Device Dynamic Fingerprinting

© 2017 SPLUNK INC.
Insider Treats External Threats
▶ Account Takeover
• Privileged account compromise
• Data exfiltration
▶ Lateral Movement
• Pass-the-hash kill chain
• Privilege escalation
▶ Suspicious Activity
• Misuse of credentials
• Geo-location anomalies
▶ Malware Attacks
• Hidden malware
activity
▶ Botnet, Command & Control
• Malware beaconing
• Data leakage
▶ User & Entity Behavior
Analytics
• Suspicious behavior by accounts
or devices
Splunk UBA Use Cases

© 2017 SPLUNK INC.
▶ ~100% of breaches involve valid credentials (Mandiant Report)
▶ Need to understand normal & anomalous behaviors for ALL users
▶ UBA detects Advanced Cyberattacks and Malicious Insider Threats
▶ Lots of ML under the hood:
• Behavior Baselining & Modeling
• Anomaly Detection (30+ models)
• Advanced Threat Detection
▶ E.g., Data Exfil Threat:
• “Saw this strange login & data transferfor user kwestin
at 3am in China…”
• Surface threat to SOC Analysts
Splunk User Behavior Analytics (UBA)

© 2017 SPLUNK INC.
Raw Security
Events
Anomalies Anomaly Chains
(Threats)
Machine
Learning
Graph
Mining
Threat
Models
Lateral Movement
Beaconing
Land-Speed Violation
HCI
Anomalies graph
Entity relationship graph
Kill chain sequence
Forensic artifacts
Threat/Risk scoring
Feedback

© 2017 SPLUNK INC.
Overall Architecture
Real-Time Infra
(Storm-based)
FilterEvents
DropEvents
Model Execution &
Online Training
Runtime
Topologies
Threat and
Anomaly Review
Hadoop/HDFS
Data
Receivers
(flume, REST, etc.)
Real-Time
Updates/Noti
fications
App/SaaS
Connectors
Core + ES
Network Data
Push/Pull Model
Persistence
Layer
DataDistributed
Kafka
ETL
IR
Model
Parsers
Filters
Attribution
ControlPath–Resource/HealthMonitoring
HBase/HDFS
Direct Access
Façade
GraphDB
SQL Access
Layer
Node.js
Socket.io
server
SQL Store
(Threats/
Anomalies)
Time-Series DBModel
Registry
Model
Store HBase
Model N
Data
Model 1
Model N
Model 1
Model N
Neo4J
(Graph
visualizations)
Rules
Engine
Anomalies
+ Threats
Analytics
Store
Syslog and
Other Data

© 2017 SPLUNK INC.
Data Flow and System Requirements
API CONNECTOR
SYSLOG
FORWARDER
Explore Visualize ShareAnalyze Dashboards
Results
THREAT & ANOMALY DATA
Query
UBA
Request for
additional
details
Threats
Results
Query
Notable events
Risk scoring framework
Workflow management
VM
Search
head
Standard RT Query
VM specs:
- Ubuntu/RHEL
- 16 cores
- 64 GB RAM
- Local and network disks
- GigE connectivity
Performance/scale:
- UBA v2.3
- E.g., 5-nodes
- 25K EPS
- Add nodes for near-linear scale
Splunk Enterprise:
- RT search capability
- 8-10 concurrent
searches
- REST API port
(8089)
- SA-LDAPSEARCH
Shared network storage

© 2017 SPLUNK INC.
▶ Security Readiness Workshop
▶ Data Science Workshop
▶ Enterprise Security Benchmark Assessment
▶ Boss of the SOC
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