In the event that your Windows machine has been compromised . in any case, don’t know where to hope to locate the awful folks’ nearness? This cheat sheet is intended to help Windows Administrators and security personnel to better execute and inside and out examination of their framework keeping in mind the end goal to search for indications of compromise .

Windows Cheat Sheet

1.Unusual Log Entries :

Check your logs for suspicious events, such as:

  • “Event log service was stopped.”
  • “Windows File Protection is not active on this system.”
  • “The protected System file [file name]was not restored to its original, valid version because the Windows File Protection…”
  • “The MS Telnet Service has started successfully.”
  • Look for large number of failed logon attempts or locked out accounts.

To do this using the GUI, run the Windows event viewer:
C:\> eventvwr.msc

Using the command prompt:
C:\> eventquery.vbs | more

Or, to focus on a particular event log:
C:\> eventquery.vbs /L security

2.Unusual Processes and Services :

Look for unusual/unexpected processes, and focus on processes with User Name “SYSTEM” or “Administrator” (or users in the Administrators’ group). You need to be familiar with normal processes and services and search for deviations.

Using the GUI, run Task Manager:
C:\> taskmgr.exe

Using the command prompt:
C:\> tasklist
C:\> wmic process list full

Also look for unusual services.
Using the GUI:
C:\> services.msc

Using the command prompt:
C:\> net start
C:\> sc query

For a list of services associated with each process:
C:\> tasklist /svc

3.Unusual Files and Registry Keys

Check file space usage to look for sudden major decreases in free space, using the GUI (right-click on partition), or type:
C:\> dir c:\

Look for unusually big files:
Start–> Search–>For Files of Folders… Search Options–>Size–>At Least 10000KB

Look for strange programs referred to in registry keys associated with system start up:

Note that you should also check the HKCU counterparts (replace HKLM with HKCU above).
Using the GUI:
C:\> regedit

Using the command prompt:
C:\> reg query

4.Unusual Network Usage

Look at file shares, and make sure each has a defined business purpose:
C:\> net view \\

Look at who has an open session with the machine:
C:\> net session

Look at which sessions this machine has opened with other systems:
C:\> net use

Look at NetBIOS over TCP/IP activity:
C:\> nbtstat –S

Look for unusual listening TCP and UDP ports:
C:\> netstat –na

For continuously updated and scrolling output of this command every 5 seconds:
C:\> netstat –na 5

The –o flag shows the owning process id:
C:\> netstat –nao 5

The –b flag shows the executable name and the DLLs loaded for the network connection.
C:\> netstat –naob 5

Note that the –b flag uses excessive CPU resources.
Again, you need to understand normal port usage for the system and look for deviations.

Also check Windows Firewall configuration:
C:\> netsh firewall show config

5.Unusual Scheduled Tasks

Look for unusual scheduled tasks, especially those that run as a user in the Administrators group, as SYSTEM, or with a blank user name.

Using the GUI, run Task Scheduler:
Start–>Programs–>Accessories–>System Tools–>Scheduled Tasks

Using the command prompt:
C:\> schtasks

Check other autostart items as well for unexpected entries, remembering to check user autostart directories and registry keys.

Using the GUI, run msconfig and look at the Startup tab:
Start –> Run, msconfig.exe

Using the command prompt:
C:\> wmic startup list full

6.Unusual Accounts

Look for new, unexpected accounts in the Administrators group:
C:\> lusrmgr.msc

Click on Groups, Double Click on Administrators, then check members of this group.
This can also be done at the command prompt:
C:\> net user
C:\> net localgroup administrators

7.Other Unusual Items

Look for unusually sluggish performance and a single unusual process hogging the CPU:
Task Manager –> Process and Performance tabs

Look for unusual system crashes, beyond the normal level for the given system.

On a periodic basis (daily, weekly, or each time you logon to a system you manage,) run through these quick steps to look for anomalous behavior that might be caused by a computer intrusion. Each of these commands runs locally on a system.

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