// CyberDefenders  ·  writeup

Volatility Traces

CyberDefenders Volatility 3

Overview

This investigation focused on analyzing a Windows memory dump using Volatility to identify suspicious processes, persistence mechanisms, defense evasion activity, and the user account associated with malicious behavior.

Only three plugins were required: windows.psscan, windows.cmdline, and windows.getsids. The analysis revealed malicious PowerShell execution, antivirus exclusions being added, and suspicious executables linked to a specific user account.


Evidence Source

ArtifactDetail
Memory Imagememory.dmp
ToolVolatility 3

Step 1 — Identify Suspicious Parent Process

Running windows.psscan against the memory dump revealed the process hierarchy. One executable stood out — it had spawned two child PowerShell processes, which is uncommon for legitimate software.

python3 vol.py -f memory.dmp windows.psscan

psscan showing process hierarchy

pslist detail view

The parent process was suspicious by name alone — a document-themed executable with no legitimate reason to be spawning PowerShell children.


Step 2 — Analyze Process Command Lines

With the suspicious parent identified, windows.cmdline was used to extract the full command line arguments of all running processes. This is where attacker intent becomes clear.

python3 vol.py -f memory.dmp windows.cmdline

cmdline output

psscan detail

Both PowerShell processes were launched with parameters targeting Windows Defender’s exclusion list using Add-MpPreference with -ExclusionPath. This is a well-known defense evasion pattern — the malware is carving out a safe zone for itself before executing its payload.

A secondary executable was also identified as active under the same parent — a persistence mechanism designed to survive reboots.


Step 3 — Map to MITRE ATT&CK

The PowerShell activity maps directly to a specific sub-technique. Modifying antivirus exclusion settings falls under Impair Defenses — the adversary is not disabling AV entirely (which would alert), but surgically excluding their own tools from scanning.

MITRE ATT&CK T1562.001


Step 4 — Identify Associated User Account

The final step linked the malicious processes to a local user account using windows.getsids, filtering for PowerShell processes. The SID mapping revealed which account the attacker was operating under.

python3 vol.py -f memory.dmp windows.getsids | grep -i powershell

getsids output showing associated user


IOCs

TypeValue
Suspicious Parent (PID 4596)InvoiceCheckList.exe
Persistence ExecutableHcdmIYYf.exe
Child Processespowershell.exe ×2
Additional Process (PID 4596)RegSvcs.exe
Associated UserLee
MITRE TechniqueT1562.001

Lessons Learned

psscan scans physical memory directly — it catches processes unlinked from the standard process list to evade detection. cmdline reveals attacker intent more clearly than any other artifact; the PowerShell parameters here told the whole story. Pairing getsids with process filtering is an efficient way to pivot from process to user context.

The use of Add-MpPreference as a defense evasion technique is worth adding to your detection playbook — it is legitimate PowerShell, which means it rarely triggers alerts on its own. Behavioral detection (PowerShell spawned from a document-themed executable) is the more reliable signal.

The investigation successfully identified the malicious process chain, persistence mechanism, defense evasion technique, and associated user account using three focused Volatility plugins. A narrow, methodical approach was more effective than running every available plugin.


Lab Questions

What is the name of the suspicious process that spawned two malicious PowerShell processes?
Click flag to revealInvoiceCheckList.exe
Which executable is responsible for the malware's persistence?
Click flag to revealHcdmIYYf.exe
Aside from the PowerShell processes, what other active suspicious process originating from the same parent is identified?
Click flag to revealRegSvcs.exe
What PowerShell cmdlet is used by the malware for defense evasion?
Click to reveal answerAdd-MpPreference
Which two applications were excluded by the malware from antivirus scanning?
Click to reveal answerInvoiceCheckList.exe, HcdmIYYf.exe
What is the specific MITRE sub-technique ID associated with disabling or modifying antivirus settings?
Click to reveal answerT1562.001
Which user account is linked to the malicious processes?
Click to reveal answerLee