COEN 250 Computer Forensics Windows Life Analysis

Extracting Evidence from a Life System Degrees of Volatility of Data. Gathering more volatile data versus Safer forensics procedures.

Extracting Evidence from a Life System Life Examination is done: To quickly access the situation Confirmation of incident. To retrieve volatile data Such as network connections, running processes, etc.

Extracting Evidence from a Life System Initial response must not destroy potential evidence. Use only trusted tools on a response toolkit. Document results. Notebook  Hard Drive of target system  Removable media connected to target drive Other system using netcat or cryptcat

Extracting Evidence from a Life System Plan investigation. Evidence gathering differs according to incidence: Unacceptable web-surfing. Intellectual property rights theft. Compromised system.

Extracting Evidence from a Life System Response Toolkit Collection of Trusted Tools. Stored on removable media. Floppies (write-protected) CD Thumbdrive (write-protected)

Response Toolkit Determine the tools needed. Create Toolkit. Check dependencies on DLL and other files. Include those in toolkit. Include a file authentication tool such as MD5.

Tools

Response Toolkit: cmd.exe Built-in command prompt should be included in the toolkit.

Response Toolkit Tool Collection System & Time Logged on Users Process Information Network and Port Information

Response Toolkit: Time and date Built-in: date /t time /t Systeminfo.exe gives uptime with a lot of other details. Perl: print localtime(time) “\n”;

Response Toolkit Logged on / remotely logged on users: PsLoggedOn (see below) Netusers from Somarsoft Net session (native to windows) rasusers (see below)

Response Toolkit rasusers Which users have remote access privileges on the target system.

Response Toolkit PsLoggedOn

Response Toolkit Process Information

Response Toolkit Pulist (from resource kit) PsList

Response Toolkit ListDLL

Response Toolkit Handle gives all handles

Response Toolkit Tlist is part of the Microsoft debugging tools.

Response Toolkit Cmdline from Diamond CS displays all processes with their arguments.

Response Toolkit PmDump dumps memory of a process.

Response Toolkit dd for windows dumps the contents of main memory into a file.

Response Toolkit Clipboard contents can be dumped with a small perl script: use Win32::Clipboard; print Win32::Clipboard->Get(), "\n";

Response Toolkit Doskey /history

Response Toolkit SC.exe communicates with the NT Service Controller

Response Toolkit Windows has “protected storage”. Use PStoreView to access it.

Response Toolkit PsService views services:

Response Toolkit PsInfo contains interesting system data including the uptime

Resource Toolkit: kill Get it from the Windows NT Resource Kit. Terminates processes via process number.

Response Toolkit Network and Port Information

Response Toolkit netstat Enumerates all listening ports and all connections to those ports.

Response Toolkit Fport Finds open TCP/IP and UDP ports and maps them to the owning application

Response Toolkit ipconfig

Response Toolkit Promiscdetect Figures out whether network card is in promiscuous mode.

Resource Toolkit: nbtstat

Response Toolkit psfile

Response Toolkit openports

Resource Toolkit: arp

Recourse Toolkit: md5sum Creates MD5 hashes for a file.

Resource Toolkit: PsLogList Dumps the event log list.

Resource Toolkit: PsInfo Local System built.

Remote Toolkit: PsFile

Resource Toolkit: PsService

Resource Toolkit Analyzing files String.exe Bintext.exe Dependency Walker File Date Time Extractor for Windows Word …

Resource Toolkit: regdump

Preparing the Toolkit

Label the toolkit. Check for dependencies with Filemon or ListDLL. Lots of dependencies  lots of MAC changes. Lots of dependencies  easy to run into a trojaned utility Create an MD5 of the toolkit. Write protect any floppies.

Using the Toolkit

Storing Obtained Data Save data on the hard drive of target.  (Modifies System.) Record data by hand.  Save data on removable media. Includes USB storage. Save data on a remote system with netcat or cryptcat.

Storing Obtained Data with netcat Quick on, quick off target system. Allows offline review. Establish a netcat listener on the forensic workstation. Redirect into a file. Establish a netcat funneler on the target system to the forensic workstation. Cryptcat does the same, but protects against sniffing.

Obtaining Volatile Data Store at least System date and time. List of current users. List of current processes. List of currently open sockets. Applications listed on open socket. List of systems with current or recent connections to the system.

Obtaining Volatile Data: Procedure Execute a trusted cmd.exe Record system time and date. Determine who is logged on. Record file MAC. Determine open ports. List all apps associated with open ports.

Obtaining Volatile Data: Procedure List all running processes. List current and recent connections. Record the system time and date. Document the commands used during initial response.

Recording System Time

Determining Logons

Cmdline from DiamondCS

Determining File MAC

Determining Open Ports

Listing Applications with Open Ports

Listing all running processes

List current connections

Documenting history

Scripting the response

Examples Use Fport to look at open ports. Use a list of ports to find suspicious ports, i.e. those used by known Trojans, sniffers or spyware.

Examples If at your home system, fport shows a suspicious port use and netstat shows a current connection to this port, then kill the process.

Examples Knowing what processes are running does not do you any good. You need to know what they are doing. At least, know the typical processes.

Examples Access the registry with RegDump Then study it with regedit on the forensic system.

Examples Assume generic monitoring of systems. Look for Unusual resource utilization or process behavior. Missing processes. Added processes. Processes with unusual user identification.

Examples The windows task manager can be very helpful.

Examples: Detecting and Deleting Trojans Use port scanning tools, either on host machine or remote machine. Fport (Windows) Superscan (Windows) Nmap netstat (for open connections)

Examples: Detecting and Deleting Trojans Identify the Trojan on the disk. Find out how it is being initiated and prevent the process. Reboot the machine and delete the Trojan.

Example Run superscan on local host to check for open ports. What is happening at port 5000?

Example Port 5000?

Example Run fport. Connected to process 1260.

Example Use pllist to find out what this is. Connected to a process called svchost.

Example Do an internet search on svchost. Process checks the service portion of the registry to start services that need to run. Use Tasklist /SVC in a command prompt

Example

Nothing serious here. At least not on the surface.