Date post: | 15-Apr-2017 |
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Searching Logs for Hackers, what you need to know to catch them
Michael Gough – FounderMalwareArchaeology.com
Co-creator of
MalwareArchaeology.com
•SAINTCON - Searching Logs for Hackers, what you need to know to catch them
Who am I
• Blue Team Defender Ninja, Malware Archaeologist, Logoholic
• I love “properly” configured logs – they tell us Who, What, Where, When and hopefully How
Creator of
• Malware Management Framework
• Several Windows Logging Cheat Sheets
• Co-Creator of “Log-MD” – Log Malicious Discovery Tool
– With @Boettcherpwned – Brakeing Down Security PodCast• @BrakeSec
• @HackerHurricane and also my Blog
MalwareArchaeology.com
• We discovered this in May 2012
• Met with the Feds ;-)
Why you should listen to me?
2014 - We gave an infected VM to one of the Big IR Firms… They came back “Yup.. It’s clean” #Fail
MalwareArchaeology.com
And because you want to catch these guys… or worse
• Ben Ten (Not PowerShell)
• Carlos (MetaSploit)
• Dave (SET)
• Kevin too (Pen Tester)
MalwareArchaeology.com
Malware evolves
• So must we
• Darwin says so
• Evolve or die
• Well… Evolve or get breached anyways
• Getting breached means an RGE !!!– Resume Generating Event
MalwareArchaeology.com
DBIR 2016
• Why we are here…
7
Time it takes hackers to compromise you
Time it takes hackers to steal your data
GOAL To catch them BEFORE data loss occurs
MalwareArchaeology.com
DBIR 2016
Hackers time to Compromise is getting faster
Than our ability to Discover them
MalwareArchaeology.com
Chasing Hashes
• Malware hashes are no longer similar
• Malware is morphing or created unique by design for each system OR on reboot
MalwareArchaeology.com
Sophos Says…
• 70% of malware is unique to 1 company (APT)• 80% of malware is unique to 10 or less (APT)• That means…• 20% of malware is what the AV industry focuses
on, but it is what most of you and everyone in this room sees and gets by:– Attachments in email– URL in email– Surfing the web
• Ads• WordPress, Drupal, Joomla…
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Winnti - Malware Infection
Malware Launch
Hiding malwarein the Registry
Modify Service
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Escalate permissions obvious NOT your admin
Check the Service used
Modify Permissions
Push out malware using CMD Shell & CScript
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Using the Registry for storage
Update Registry
Change Registry Permissions
Change permissions on files
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Bad behavior becomes obvious
Doing Recon
Going after Terminal Services
Query Users
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Persistence
• Avoided leaving key files behind like they did before, well one anyways… the persistence piece
MalwareArchaeology.com
HKLM\Software\Clients
• putfile
• file
• read
4D5A = MZ in HEXKey Size = 256k
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Persistence
• Infector… One for the DLL (infect.exe) and one for the Driver (InfectSys.exe)
• Altered system management binaries
– McAfeeFrameworkService
– BESClientHelper
– Attempted a few others, some failed
MalwareArchaeology.com
Angler delivered Kovter
• Unique way to hide the persistence
• Inserted a null byte in the name of the \Run key so that RegEdit and Reg Query fail to read and display the value
• And a LARGE Reg Key (anything over 20k is large)
MalwareArchaeology.com
Dridex Persistence
• New method towards the end of 2015, nothing in the Registry showing persistence while system was running
• In memory only until system shutdown
– On shutdown the Run key was created
• On startup the malware loads and Run key deleted
MalwareArchaeology.com
Where to start
• What am I suppose to set?
“Windows Logging Cheat Sheet”
“Windows File Auditing Cheat Sheet”
“Windows Registry Auditing Cheat Sheet”
“Windows Splunk Logging Cheat Sheet”
“Malware Management Framework”
• Find them all here:
– MalwareArchaeology.com
MalwareArchaeology.com
PowerShell
• It’s coming… in a BIG way - It’s already here• Ben Ten uses it (Not PowerShell)• Carlos uses it (MetaSploit)• Dave uses it (SET)• Kevin too (Pen Tester)• Dridex uses it• RansomWare uses it
• And Windows default logging is TERRIBLE for it!
MalwareArchaeology.com
So what do we do about PowerShell?
• The “Windows PowerShell Logging Cheat Sheet”
• Designed to catch the folks I just mentioned, and others ;-)
• Get it at:
– MalwareArchaeology.com
MalwareArchaeology.com
How to catch this stuff
Enable Command Line Logging !!!!
• At the time of Winnti 2014 ONLY Win 8.1 and Win 2012 R2 had command line logging
• Which we had, then we saw this in our alerts of suspicious commands (Cscript & cmd.exe & cacls & net & takeown & pushd & attrib)
• SIX Commands
• Scripts too
MalwareArchaeology.com
And this query - Splunk
• index=windows LogName=Security EventCode=4688 NOT (Account_Name=*$) (arp.exe OR at.exe OR bcdedit.exe OR bcp.exe OR chcp.exe OR cmd.exe OR cscript.exe OR csvde OR dsquery.exe OR ipconfig.exe OR mimikatz.exe OR nbtstat.exe OR nc.exe OR netcat.exe OR netstat.exe OR nmap OR nslookup.exe OR netsh OR OSQL.exe OR ping.exe OR powershell.exe OR powercat.ps1 OR psexec.exe OR psexecsvc.exe OR psLoggedOn.exe OR procdump.exe OR qprocess.exe OR query.exe OR rar.exe OR reg.exe OR route.exe OR runas.exe OR rundll32 OR schtasks.exe OR sethc.exe OR sqlcmd.exe OR sc.exe OR ssh.exe OR sysprep.exe OR systeminfo.exe OR system32\\net.exe OR reg.exe OR tasklist.exe OR tracert.exe OR vssadmin.exe OR whoami.exe OR winrar.exe OR wscript.exe OR "winrm.*" OR "winrs.*" OR wmic.exe OR wsmprovhost.exe OR wusa.exe) | eval Message=split(Message,".") | evalShort_Message=mvindex(Message,0) | table _time, host, Account_Name, Process_Name, Process_ID, Process_Command_Line, New_Process_Name, New_Process_ID, Creator_Process_ID, Short_Message | stats count > 2
MalwareArchaeology.com
So how do you do this?
• Malware Management allowed us to setup alerts on artifacts from other malware analysis– MalwareManagementFramework.org
• Of course our own experience too
• Malware Discovery allowed us to find odd file hashes, command line details, registry locations
• Malware Analysis gave us the details
MalwareArchaeology.com
What we all need to look for
• Logs of course, properly configured - Events– Command Line details– Admin tools misused – executions– New Services (retail PoS should know this)– Drivers used (.sys)
• New Files dropped anywhere on disk – Hashes– Infected management binary (hash changed)
• Delete on startup, write on shutdown – File & Reg Auditing• Scripts hidden in the registry – Registry Compare• Payload hidden in the registry – Large Reg Keys• Malware Communication – IP and WhoIS info• Expand PowerShell detection• VirusTotal Lookups
MalwareArchaeology.com
You basically have 3 options
• Do nothing – Eventually leading to an RGE
• Log Management / SIEM
– Cost $$$ and storage
– But IS the best option, better than most security solutions if you want my opinion
• What if you don’t have Log Management or a SIEM?
MalwareArchaeology.com
• Log and Malicious Discovery tool
• When you run the tool, it tells you what auditing and settings to configure that it requires. LOG-MD won’t harvest anything until you configure the system!
• So answers How to check for the What to set I already told you about
MalwareArchaeology.com
Audit first
• Audit Report of log settings compared to:
– The “Windows Logging Cheat Sheet”
– Center for Internet Security (CIS) Benchmarks
– Also USGCB and AU ACSC
• Plain text report so you can include them in your own report format
MalwareArchaeology.com
Purpose
MalwareArchaeology.com
• Malware Analysis Lab – Why we initially developed it• Investigate a suspect system• Audit the Windows - Advanced Audit Policy settings• Help MOVE or PUSH security forward• Give the IR folks what they need and the Feds too• Take a full system (File and Reg) snapshot to compare to another
system and report the differences• Discover tricky malware artifacts (Large Keys, Null Byte, AutoRuns)• SPEED !• Deploy with anything you want, SCCM, LanDesk, PSExec, PS, etc…• Replace several tools we use today with one easy to use utility that
does much more• Replace several older tools and GUI tools• To answer the question: Is this system infected or clean?• And do it quickly !
Free Edition
MalwareArchaeology.com
• Audit your settings – Do you comply?• Harvest security relevant log data• Whitelist log events by IP, Cmd Line, Process and
File / Registry audit locations• Perform a full File Baseline of a system• Compare a suspect system to a Baseline or Dir• Perform a full Registry snapshot of a system• Compare a suspect system to a Reg Baseline• Look for Large Registry Keys for hidden payloads• 12 Reports
MalwareArchaeology.com
• Everything the Free Edition does and…• 21 reports, breakdown of things to look for• Specify the Output directory• Harvest Sysmon logs• Whitelist Hash compare results• Whitelist Registry compare results• Create a Master-Digest to exclude unique files• Free updates for 1 year, expect a new release
every quarter• Manual – How to use LOG-MD Professional
MalwareArchaeology.com
Future Versions – In the works!• PowerShell details
• WhoIs lookups of IP Addresses called
• VirusTotal lookups of discovered files• Find parent-less processes• Assess all processes and create a Whitelist• Assess all services and create a Whitelist• VirusTotal lookups of unknown or new processes and
services• Other API calls to security vendors
MalwareArchaeology.com
Crypto Event
» C:\Users\Bob\AppData\Roaming\vcwixk.exe
» C:\Users\Bob\AppData\Roaming\vcwpir.exe
» C:\WINDOWS\system32\cmd.exe /c del C:\Users\Bob\AppData\Roaming\vcwixk.exe >> NUL
» C:\Windows\System32\vssadmin.exe delete shadows /all /Quiet
MalwareArchaeology.com
Use the power of Excel
• The reports are in .CSV format
• Excel has sorting and filters
• Filters are AWESOME to thin out your results
• You might take filtered results and add them to your whitelist once vetted
• Save to .XLS and format, color code and produce your report
• For .TXT files use NotePad++
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So what do we get?
• WHAT Processes executed
• WHERE it executed from
• IP’s to enter into Log Management to see WHO else opened the malware
• Details needed to remediate infection
• Details to improve your Active Defense!
• I did this in…15 Minutes!
So what do we get?
MalwareArchaeology.com
• WHAT Processes executed
• WHERE it executed from
• IP’s to enter into Log Management to see WHO else opened the malware
• Details needed to remediate infection
• Details to improve your Active Defense!
• I did this in…
15 Minutes!
Resources
MalwareArchaeology.com
• Websites– Log-MD.com The tool
• The “Windows Logging Cheat Sheet”– MalwareArchaeology.com
• Malware Analysis Report links too– To start your Malware Management program
• This presentation is on SlideShare and website– Search for MalwareArchaeology or LOG-MD