Showing posts with label Anti-forensics. Show all posts
Showing posts with label Anti-forensics. Show all posts

Friday, March 6, 2026

Windows Forensic — Audit Log Cleared

Windows Forensic — Audit Log Cleared

picoCTF เป็นเกม ด้าน computer security ที่จัดโดย มหาวิทยาลัย Carnegie Mellon หรือ CMU ที่มุ่งเป้าไปที่นักเรียนมัธยมและ มหาวิทยาลัยให้มาแสดงทักษะความสามารถ

Windows Forensic — Audit Log Cleared
photo Credit:PicoCTF

Windows Forensic — Audit Log Cleared

Description

One of the employees at your company has their computer infected by malware! Turns out every time they try to switch on the computer, it shuts down right after they log in. The story given by the employee is as follows:
  1. They installed software using an installer they downloaded online
  2. They ran the installed software but it seemed to do nothing
  3. Now every time they bootup and login to their computer, a black command prompt screen quickly opens and closes and their computer shuts down instantly.
See if you can find evidence for the each of these events and retrieve the flag (split into 3 pieces) from the correct logs!
The analysis of Windows Event Logs should follow the digital forensic methodology recommended by the National Institute of Standards and Technology (NIST SP 800-86), which includes the stages of collection, examination, analysis, and reporting.

Collection of digital evidence


1️⃣ Evidence Identification (ระบุหลักฐาน)
File Name: Windows_Logs.evtx
Source: Employee Workstation(PicoCTF) Download the Windows Log file here
Evidence Type: Windows Event Log

Windows Forensic — Audit Log Cleared


2️⃣ Evidence Preservation (การรักษาหลักฐาน)

Windows Forensic — Audit Log Cleared

#Get-FileHash Windows_Logs.evtx
MD5    checksum:       630F28FF65702E0794256E87172C39CB
SHA1    checksum:      7D242525D3A1FA26923821F9C4416A895BB3C7F6
 
Step > Action
Receive evidence> Investigator
Calculate hash > SHA1 ,MD5
Store copy > Forensic workstation

3️⃣ Create Working Copy
Windows_Logs_original.evtx > Windows_Logs_analysis.evtx
4️⃣ Evidence Examination
Forensic tools
  • Event Viewer
  • PowerShell

Examination of forensic artifacts


5️⃣ Event Log Classification
Log TypeDescription
SecurityAuthentication events
6️⃣  Identify Suspicious Events

Event ID Description
  • 1102 Audit Log Cleared
  • 1033 Windows Installer
  • 4657 Registry Value Modified
  • 1074 System Shutdown

Windows Forensic — Audit Log Cleared

Windows Forensic — Audit Log Cleared

Event Analysis: Event ID 1102 – Audit Log Cleared
The screenshot shows a Windows Security Event Log entry with Event ID 1102.
 In digital forensic investigations, Event ID 1102 is considered a highly suspicious event because it may indicate an attempt to remove evidence from the system.

Attackers or malicious software may clear logs in order to:

  • hide malicious activities

  • remove traces of system compromise

  • prevent investigators from reconstructing the attack timeline

Therefore, this event is often associated with anti-forensic behavior.

Windows Forensic — Audit Log Cleared

Event Analysis: Event ID 1033 – Windows Installer Activity
The screenshot shows a Windows Application Event Log entry with Event ID 1033, generated by the Windows Installer service. However, the Manufacturer field contains an encoded value, which is unusual and may indicate hidden information. 

cGljb0NURntFdjNudF92aTN3djNyXw== This format resembles Base64 encoding, a common encoding method used to represent binary or text data. 
Malicious software installers sometimes embed encoded or obfuscated values in metadata fields to:
  • hide commands
  • store configuration data
  • conceal indicators of compromise

Windows Forensic — Audit Log Cleared


Event ID 4657 – Registry Value Modified 
The screenshot shows a Windows Security Event Log entry with Event ID 4657, which indicates that a registry value has been modified on the system.

The presence of Event ID 4657 suggests that the installed program modified the Windows Registry, which may indicate that malware created a persistence mechanism.

Windows Forensic — Audit Log Cleared

Event ID 1074 — System Shutdown Initiated The screenshot shows a Windows System Event Log entry with Event ID 1074, which records that a process initiated a system shutdown or restart.

Relationship to the Incident Scenario

The employee reported:

1️⃣ They installed software downloaded from the internet
2️⃣ The software appeared to do nothing
3️⃣ A command prompt briefly appears during login
4️⃣ The computer shuts down immediately

The forensic evidence supports this narrative.

Evidence Correlation Timeline

Analysis and timeline reconstruction


7️⃣ Timeline Reconstruction
Time Event ID     Event

03:55:14 1102     Audit log cleared

03:55:57 1033     Software installed

03:56:19 4657     Registry modified

05:02:35 1074     System shutdown


Reporting and documentation of findings


Investigation Conclusion

The analysis of Windows Event Logs revealed a sequence of suspicious events.

Key findings include:

  • Installation of potentially malicious software

  • Registry modification suggesting persistence mechanism

  • Programmatic system shutdown initiated by shutdown.exe

These events indicate a likely malware infection affecting the system.

Further investigation should include:

  • malware analysis

  • registry artifact examination

  • disk forensic analysis

Windows Forensic — Audit Log Cleared

Windows Forensic — Audit Log Cleared

Ref: 

PicoCTF

Digital forensic analysis conducted according to:

    • NIST SP 800-86 Guide to Integrating Forensic Techniques into Incident Response

อ่านเพิ่มเติม: 


หมายเหตุ:เนื้อหาในเว็บไซต์นี้มีขึ้นเพื่อวัตถุประสงค์ในการให้ข้อมูลและเพื่อการศึกษาเท่านั้น ช่วยเตือนความจำ


* หากมีข้อมูลข้อผิดพลาดประการใด ขออภัยมา ณ ที่นี้ด้วย  รบกวนแจ้ง Admin เพื่อแก้ไขต่อไป
ขอบคุณครับ

#WindowsForensic #ComputerForensics #dfir #forensics #digitalforensics #computerforensic #investigation #cybercrime #fraud

Saturday, October 22, 2016

Digital Forensics: A Complete Anti-Forensics Guide

Digital Forensics: A Complete Anti-Forensics Guide

The average personal computer is a security nightmare, but what if i were to tell you there was a way around this, a way to make windows secure? VPNs, proxies and TOR only get you so far, but what do you do when they’ve traced it to your computer?
Anti-forensics is designed for this situation, to prevent them from proving you’ve done anything wrong even if they have your computer, its the art of leaving no trace, it is combating common forensic tools in preventing any penetration for forensic tests on your computer.
Anti-forensics can pretty much be summed up in one famous quote:
Make it hard for them to find you, and impossible for them to prove they’ve found you
– Scott Berinato.
This article will teach you everything you need to know about anti-forensics to protect you and your privacy.

1) Disabling Time Stamps

Using Time Stamps, Forensic Experts can build a “Digital Time-Line”, this can be very compelling evidence when cross referenced with other known evidence. In order to strengthen security, we must disable these logs.
a) User Assist File
In the windows registry, there are settings that store logs and there respective dates of all launched programs, forensic experts can use this information to construct a digital time-line of your activity on the computer, disabling these settings is a key aspect of anti-forensics.
HKEY_Current_User\Software\Microsoft\Windows\CurrentVersion\Explorer\UserAssist
You should see two sub-keys called “Count”, delete both these keys, Now right click the UserAssist Key and Create a new key named “Settings”, In this key create “DWORD” value named “NoLog”, and set the value to 1.
Windows will no longer store logs of your activity.
b) Last Access Logs
Next we’ll disable the last access in windows. What last access is a setting on windows that allows you to see when you opened, modified, and/or created files on your computer and is similar to the “UserAssist” registry key. By disabling this forensic experts won’t as easily be able to tell when you’ve been accessing programs or files on your computer.
To disable last access, open CMD on your computer, and type the following command,
fsutil behavior set disablelastaccess 1
After typing this command, please restart your system and make sure that you’ve to use CMD as a administrator.

Disabling Time Stamps


2) Encrypting Your Computer

It is very important to make sure that your computer is encrypted, in the case an unwanted visitor is trying to access your computer, they will not be able to access to computer if it is encrypted.
Step 1 – TRUECRYPT
To encrypt your computer, you can use Truecrypt, a free program that allow you to encrypt your computer. When encrypting with this tool, you have two options – the first one is to create a hidden container, A hidden container is an OS that is impossible prove exists.
When creating a hidden container you’ll have 3 different passwords.
  • The first would be for your decoy system, the OS you would show someone forcing you to login your computer.
  • The second password would be for your outer volume, the OS you would show someone forcing you to login to the second partition on your computer.
  • Third password is for the hidden OS on the second partition of your computer, this OS is placed in the inner volume, and is impossible to prove exists.
The 2nd Option is just encrypt your HARD-DRIVE. This is also very secure, but you may be forced to give up your password due to court-order; in this situation many would think to simply say that they forgot their password, but doing so could get you held in contempt of court. With normal drive encryption, your computer is just as secure “Encryption Wise” and you’ll have a single password.
For more info, you can even visit their official website.
TRUECRYPT

Step 2 – Encrypt Your Keystrokes
It is imperative that you protect yourself from keyloggers, hackers will use these to steal log-in information and credit cards, the government uses keyloggers to spy on you. A few years ago, there was a lot of speculation about “CIPAV”, a government owned/coded piece of spyware, which would record the victim’s IP address, MAC address, open ports, operating system, installed applications, default web browser, time and date of log-ins, visited URLs, download history, and most critically, aLL typed keystrokes (that means all your accounts log-in information, credit cards, personal emails, everything). CIPAV was a huge invasion of privacy, and should serve as a reminder that you can never be too careful.

Encrypting your keystrokes is an excellent technique to protect yourself from keyloggers, it renders any tracking of typed keystrokes completely useless.
Keyscrambler is a program which can do just that, encrypting all keystrokes sent to a variety of popular applications; its premium version supports 170+ programs, though it is not free, and costs a hefty $45, you can alternatively use the free version, but it is obsolete when compared to the premium.

3) Making Encryption Secure

Encryption is pointless if it can be easily bypassed or overcome. You need to make sure that the encryption is secure too.
Step 1 – Make Sure Your Password Is Strong
Even with your computer encrypted, it is still vulnerable. Make sure your password is good (for optimal security, your password should be twenty or more characters, with symbols, numbers, and random capitals, and a special symbol (eg, ALT+1456) really increase security).
If you password is not strong enough, you can change it by right clicking your encrypted drive in TrueCrypt and selecting ‘Change Password’.
Step 2 – Create A Locked Screen Saver
Encryption is pointless if the feds get to your computer while its running. They can use live forensic tools that don’t require the movement or shutdown of a computer. A very simple technique to overcome this is to create a locked screen saver.
To create a locked screen saver in Windows Vista or Windows 7;
Right click your desktop and click on “Personalize”. In the bottom left hand corner you should see “Screen Saver” click that. Now, check “On Resume Display Log-on  Screen”, and set “Wait” to 5.
Now you must go to your Control Panel. Click on “System and Security” now click on “Power Options” find your selected plan and click “Change plan settings”; now, set “Turn Of Display” to “5 minutes”.
Step 3 – Get A Good Anti-Virus
This may seem obvious, but all this is pointless if you get infected with a keylogger that takes screen shots. Having a good anti-virus is one of the most important things you can do. Many people make the mistake of having a poor anti-virus; AVG, Norton, McAfee, all are awful anti-viruses. The only anti-virus programs I find worthy of my recommendation are ESET Nod32, Kaspersky, and BitDefender, these anti-viruses are very good, but quality comes with a price-tag and you might find them a bit too expensive for your taste.
Anti-Virus

4) Disable and Remove USB Logs

Next on the list of Anti-Forensics in to disable logs of USB activity, flash drives, etc… This can be valuable if you have a flash drive with sensitive data and you don’t want any logs of it ever being plugged it to your computer.
Step 1 – Delete the USBSTOR Registry Setting
In your registry, there is a key called “USBSTOR”, which logs all information on USB devices interpreted by your computer; brand name and model, size of the device, date and time pluxed in, etc..
Forensic experts can and will use this to match your computer to USB devices.
Deleting this registry key is not as simple as most others, it has special permissions that can be hard to bypass. To delete this key, we will use a tool from Microsoft called “PsExec“.
Once you have it downloaded, extract the RAR file to your desktop. Open up Command Prompt (as Administrator) and type the following into the command line;
cd C:\Users\%Username%\Desktop\PsExec
This will cause Command Prompt to navigate to your desktop, once this is done type the following into the command line;
psexec -i -d -s c:\windows\regedit.exe
The Regstry Editor window will open, with full permissions. Browse to the following directory
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Enum\USBSTOR
Now, right click “USBSTOR” and hit ‘Delete’, then confirm that you want to delete the key, congratulations- the key has been deleted.
USBSTOR Registry
Step 2 – Delete The Setupapi.log File
The Setuppapi log is a plain-text file that stores the list of installed USB devices and their drivers. We will delete it with a program called “CCleaner”.
CCleaner is actually one of the best tools that anti-forensic has to offer, it does a great job of securely wiping files (assuming you have it set to delete securely), for specific instructions, see the “Wipe With CCleaner” section of the guide.

5) Windows Security Misc.

This section is for various information that is important to anti-forensics, but isn’t quite big enough to have its own section within the article.
Step 1 – Disable System Restore Points
System Restore points can be used to bring your computer back to a date when it wasn’t secure and can also be used to restore overwritten files.
To disable System Restore points, right click “Computer” and click “Properties”, Now click “Advanced System Settings” Under “System Protection”, click “Configure Now”
Select Turn Off System Protection and apply it.
Step 2 – Disable Send Error Report to Microsoft
This is self-explanatory, we obviously don’t want Microsoft having logs of all our crashed programs.
To do this, go to your start menu and search ‘problem reporting settings’ and then click on ‘Choose How To Report Problems’. Click ‘Change Report Settings For All Users’ and then set it to ‘Never check for solutions’.
Step 3 – Wipe With CCleaner
This is the heart of Anti-Forensics right here. CCleaner is actually one of the most powerful Anti-Forensic tools, IF used correctly.
As it turns out, when deleting files, you DO NOT need to do multiple overwrites. With modern hard-drives, one overwrite really is enough to delete a file beyond repair, even though it is popular belief that you need several overwrites to be secure. With CCleaner, I would recommend two overwrites, just in-case it misses something the first time around (remember, it freeware).
CCleaner
Once you have CCleaner installed, run it (as administrator), go to Settings and make sure you have it set to overwrite deleted data with three passes.
Go back to Cleaner and check everything then hit Run Cleaner. You might want to leave this on overnight depending on how many files it has to clean.
Do this every time you are done with a major hacking job. When using CCleaner normally (what should be every time you are done with your computer), uncheck Wipe Free Space this will cut down the time from hours to a few minutes.
Step 4 – Disable Debugging Upon Failure
This keeps logs of your computers failures and blue screen info. To disable it, right click Computerand go to “Advanced System Settings”, now go to “Start Up and Recovery” None, set Debugging Information to None.
Step 5 – Disable Windows Event Logging
Windows keeps logs of all events on the computer. First, before we disable, we must clear all the logs.
To disable it, go to Control Panel then System and Security. Now, click Administrative Tools, and then Event Viewer. In either pane of the Event Viewer window, right-click System and then select Clear All Events, click No to the dialog box that will open.
Now we must disable Windows Event Logging. Go to Run and type in “msconfig” then go to ‘Services’ and make sure ‘Hide all Microsoft Services’ is unchecked. Now scroll down until you find Windows Event Logging, and uncheck it.
Now restart your computer right away.
Step 6 – Disable Windows Hibernation
You may as well hand your computer over to the feds if they raid your house and your computer is in hibernation. Also, putting your computer into hibernation is pretty much just taking a screen shot of your RAM that gets saved to your hard drive.
Open your Control Panel. Click System and Security, then click ‘Power Options’, Click ‘Change plan settings’ for you current power plan.
Now click “Change advanced power settings” Expand “Sleep” then expand “Hibernate After” Enter 0 for Setting
Hibernation is now disabled.
Step 7 – Disable Stand By In Registry
Disabling standby is necessary for the same reasons that disabling hibernation is. For this step, I have prepared a pre-written code;
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ACPI\Parameter…
Simply create a new text file on your desktop, paste the above code in it, and save it has standby.reg then double click the .regfile and click Ok to dialog box that will appear.
…All Credit Goes to r00t3r[dot]com (Saurfang)

yeahhub

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* หากมีข้อมูลข้อผิดพลาดประการใด ขออภัยมา ณ ที่นี้ด้วย  รบกวนแจ้ง Admin เพื่อแก้ไขต่อไป
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#WindowsForensic #ComputerForensics #dfir #forensics #digitalforensics #computerforensic #investigation #cybercrime #fraud 

Saturday, September 28, 2013

Digital Forensics: Remove hidden data and personal information

Digital Forensics: Inspect Document

  เป็นฟังก์ชันสำหรับการลบข้อมูล metadata ออกจากเอกสาร  Office documents เช่น Word, Excel , PowerPoint  ทำให้ยากต่อการติดตามร่องรอย
    hidden data or personal information that you might not want to share in Office documents


  1. Open the Power point presentation  that you want to inspect for hidden data and personal information.
    Windows Forensic Presentation
    Tile: Windows Forensic ; Authors: Stephen Rondeau
     ตรวจสอบค่า Hash value
    Hash Value MD5 & SHA
  2. Click the File tab, click Save As, and then type a name in the File name box to save a copy of your original presentation.


  3. In the copy of your original presentation , click the File tab, and then click Info. 



  4. Click Check for Issues, and then click Inspect Presentation.

  5. In the Presentation Inspector dialog box, select the check boxes to choose the types of hidden content that you want to be inspected.

  6. Click Inspect.

    Remove personal information

  7. Review the results of the inspection in the Presentation Inspector dialog box.
    Tile, Authors ,Last save by

  8. Click Remove All next to the inspection results for the types of hidden content that you want to remove from your Presentation.
hash value mismatch

สรุปการใช้งาน   Inspect Office Document

  • สามารลบข้อมูล metadata ได้
  • ทำให้ค่า hash เปลี่ยนแปลง 

     

ที่มา:

support.office.com


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* หากมีข้อมูลข้อผิดพลาดประการใด ขออภัยมา ณ ที่นี้ด้วย  รบกวนแจ้ง Admin เพื่อแก้ไขต่อไป
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#WindowsForensic #ComputerForensics #dfir #forensics #digitalforensics #computerforensic #investigation #cybercrime #fraud 

Saturday, March 31, 2012

Digital Forensics: Anti-forensics

Digital Forensics: Anti-forensics

Anti-Forensics: Occult Computing Class
This is a class I gave for the Kentuckiana ISSA on the the subject of Anti-forensics. It's about 3 hours long, and sort of meandering,

Anti-Forensics: Occult Computing Class



Ref:


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* หากมีข้อมูลข้อผิดพลาดประการใด ขออภัยมา ณ ที่นี้ด้วย  รบกวนแจ้ง ADMIN เพื่อแก้ไขต่อไป
ขอบคุณครับ

#WINDOWSFORENSIC #COMPUTERFORENSICS #DFIR #FORENSICS #DIGITALFORENSICS #COMPUTERFORENSIC #INVESTIGATION #CYBERCRIME #FRAUD 


Saturday, July 17, 2010

Digital Forensics: Anti-forensics


Digital Forensics: Anti forensics


Anti forensics คือ

การใช้เทคนิคซ่อนหรือทำลายข้อมูลเพื่อไม่ให้สามารถตรวจพิสูจน์พยานหลักฐานได้หรือทำได้ลำบาก (Anti-forensics) เช่น การใช้ซอฟต์แวร์ลบข้อมูล 

Encryption

Anti forensics หมายถึง

การต่อต้านการพิสูจน์หลักฐานทางคอมพิวเตอร์ (บางครั้งการตอบโต้ทางนิติเวช) เป็นคำทั่วไปสำหรับชุดของเทคนิคที่ใช้เป็นวิธีการรับมือกับการวิเคราะห์ทางนิติเวช


Anti-forensics

Anti-Forensics คือ 

การใช้วิธีการและเครื่องมือเพื่อทำให้รอดพ้นจากการตรวจพิสูจน์พยานหลักฐาน โดยการลบหรือแก้ไขข้อมูล ,การสร้าง ทำให้เสียเวลาและการซ่อนข้อมูล การสร้างหลักฐานปลอม การใช้ประโยชน์จากข้อบกพร่องของการใช้งานในเครื่องมือที่รู้จัก และลบร่องรอยออกจากข้อมูล เพื่อป้องกันผู้ติดตาม 

wiping

Anti Forensics คือ

ความพยายามใช้วิธีการและเครื่องมือที่จะส่งผลเสียต่อการดำรงอยู่ของจำนวนและคุณภาพของพยานหลักฐานจากที่เกิดเหตุหรือยากต่อทำการวิเคราะห์และตรวจสอบหลักฐานหรือเป็นไปไม่ได้ที่จะดำเนินการตรวจพิสูจน์พยานหลักฐาน

ที่มา:
Anti-computer_forensics
Anti-forensics_Techniques_detection
6-anti-forensic-techniques-that-every-cyber-investigator

หมายเหตุ:เนื้อหาในเว็บไซต์นี้มีขึ้นเพื่อวัตถุประสงค์ในการให้ข้อมูลและเพื่อการศึกษาเท่านั้น

* หากมีข้อมูลข้อผิดพลาดประการใด ขออภัยมา ณ ที่นี้ด้วย  รบกวนแจ้ง Admin เพื่อแก้ไขต่อไป
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#WindowsForensic #ComputerForensics #dfir #forensics #digitalforensics #computerforensic #investigation #cybercrime #fraud

Volatility Lab

Volatility Lab  Image Wanna.vmem P.73 windows.info #python3  vol.py   -f '/home/kali/Desktop/Wanna/Wanna-MEM.vmem' windows.info     ...