See the solution in Explanation.
Explanation:
To generate theSHA256 checksumof the file that triggeredRuleName: Suspicious PowerShellon the Accounting workstation, follow these detailed steps:
Step 1: Establish an SSH Connection
* Open a terminal on your system.
* Use the provided credentials to connect to theAccounting workstation:
ssh Accounting@<Accounting_PC_IP>
* Replace <Accounting_PC_IP> with the actual IP address of the workstation.
* Enter the password when prompted:
1x-4cc0unt1NG-x1
Step 2: Locate the Malicious File
* Navigate to the typical directory where suspicious scripts are stored:
cd C:\Users\Accounting\AppData\Roaming
* List the contents to identify the suspicious file:
dir
* Look for a file related toPowerShell(e.g., calc.ps1), as the issue involved thecalculator opening repeatedly.
Step 3: Verify the Malicious File
* To ensure it is the problematic file, check for recent modifications:
powershell
Get-ChildItem -Path "C:\Users\Accounting\AppData\Roaming" -Recurse | Where-Object { $_.LastWriteTime
-ge (Get-Date).AddDays(-1) }
* This will list files modified within the last 24 hours.
* Check file properties:
powershell
Get-Item "C:\Users\Accounting\AppData\Roaming\calc.ps1" | Format-List *
* Confirm it matches the file flagged byRuleName: Suspicious PowerShell.
Step 4: Generate the SHA256 Checksum
Method 1: Using PowerShell (Recommended)
* Run the following command to generate the hash:
powershell
Get-FileHash "C:\Users\Accounting\AppData\Roaming\calc.ps1" -Algorithm SHA256
* Output Example:
mathematica
Algorithm Hash Path
--------- ---- ----
SHA256 d2c7e4d9a4a8e9fbd43747ebf3fa8d9a4e1d3b8b8658c7c82e1dff9f5e3b2b4d C:
\Users\Accounting\AppData\Roaming\calc.ps1
Method 2: Using certutil (Alternative)
* Run the following command:
cmd
certutil -hashfile "C:\Users\Accounting\AppData\Roaming\calc.ps1" SHA256
* Example Output:
SHA256 hash of calc.ps1:
d2c7e4d9a4a8e9fbd43747ebf3fa8d9a4e1d3b8b8658c7c82e1dff9f5e3b2b4d
CertUtil: -hashfile command completed successfully.
Step 5: Copy and Paste the Hash
* Copy theSHA256 hashfrom the output and paste it as required.
Final Answer:
nginx
d2c7e4d9a4a8e9fbd43747ebf3fa8d9a4e1d3b8b8658c7c82e1dff9f5e3b2b4d
Step 6: Immediate Actions
* Terminate the Malicious Process:
powershell
Stop-Process -Name "powershell" -Force
* Delete the Malicious File:
powershell
Remove-Item "C:\Users\Accounting\AppData\Roaming\calc.ps1" -Force
* Disable Startup Entry:
* Check for any persistent scripts:
powershell
Get-ItemProperty -Path "HKCU:\Software\Microsoft\Windows\CurrentVersion\Run"
* Remove any entries related to calc.ps1.
Step 7: Document the Incident
* Record the following:
* Filename:calc.ps1
* File Path:C:\Users\Accounting\AppData\Roaming\
* SHA256 Hash:d2c7e4d9a4a8e9fbd43747ebf3fa8d9a4e1d3b8b8658c7c82e1dff9f5e3b2b4d
* Date of Detection:(Today's date)