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Welcome to M-unition, the MANDIANT blog. Here we share our insights about the tools we create and use to find evil and solve crime.

Memory acquisition and the pagefile(s)

Written by Jamie Butler

In the past, I have discussed how in reality there may be as many as 16 pagefiles on a single host. The next question is, “How much data could be contained in all these pagefiles”? Why does this matter? Well, the more data in the pagefiles, the longer they will take to acquire.
 
The size of the pagefiles usually depends on the amount of RAM in the host. If you allow Windows to automatically configure the pagefile(s), it will typically recommend that the total size of the pagefiles should be 1.5 times the size of RAM. Here is an example of the recommended settings on a host with 3.5 GB of memory.

The recommended total pagefile size is 5,371 MB or approximately 1.5 times 3.5 GB. However, you can configure the pagefiles manually. Some Web sites suggest making the size of the pagefile(s) as much as 3 times the size of RAM. This is what Microsoft has suggested as the maximum size for better performance on Windows XP.
 
As pagefiles get bigger, they will take longer to acquire. Let’s look at how large they could be in x64 / EM64T, which is generically referred to as 64bit. On 64bit Windows hosts, 32bits or 2^32 are used to represent the offset in the pagefile where the page was stored. Each page in the pagefile is 4096 bytes or 2^12. We know there can be as many as 16 pagefiles or 2^4. Putting it all together:
 
(Pagefile Offset) * (Page Size) * (Number of Pagefiles) = Total Size of Paging Data
 
(2^32) * (2^12) * (2^4) = Total Size of Paging Data
 
2^48 = Total Size of Paging Data
 
281,474,976,710,656 = Total Size of Paging Data
 
256 TB = Total Size of Paging Data

Now, I know 256 TB is not going to be typical, but acquiring even 4 GB to 12 GB of paging files can take a long time. The pagefiles are in use and locked by the operating system. To gain access, tools typically parse the filesystem for access to the sectors that represent the pagefiles. This prolongs the time required to acquire the files.
 
Next time in this series, we will discuss more about time and its implication on the paging files. If this series is boring you, the memory forensics class at Black Hat contains more hands-on applications and use cases. This year, Aaron LeMasters, author of Web Historian 2.0, will be helping with the class. I hope to see you there.

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. 07 Jul 10 | General | Comments (3)

New Memoryze, Audit Viewer, and Training

Written by Jamie Butler

For those who are not on our mailing list for Memoryze or Audit Viewer, we released a new version a little over a week ago. The new version of the software includes all of the memory analysis features that are available in the newly released MANDIANT Intelligent Response (MIR) 1.4.
 

So what is included in Memoryze and Audit Viewer 1.4? Well, here is the short of it.
 

Memoryze:

  • Support for Windows 2003 x64 SP2
  • Improved support of Vista SP1 and SP2 including port enumeration and a better installer
  • Enumeration of digital signatures for all loaded modules in a processes’ address space, hooked and hooking drivers, and all drivers found by driver signature scans
  • Enumeration of MD5/SHA1/SHA256 hash on disk for all loaded modules in a process’ address space and all drivers found by driver signature scans
  • Updated documentation
  • Single installer for 64-bit and 32-bit versions

 
Audit Viewer:

  • Improvements to the Malware Rating Index (MRI)
  •      Report visualization of MRI results
  •      MRI rule editors that will allow users to graphically edit the MRI rule file
  •      Handle Trust view to help identify suspicious handles
  • Ability to search results within a specific process
  • Multi-select with copy
  • Multi-select and export to a CSV file

 
Those who attended the CanSecWest Training in March have already been enjoying many of these features in beta form for months, and we are committed to ensuring that those who attend the Advanced Memory Forensics in Incident Response class at Black Hat will get early access to the next version of Memorzye, which will support Windows 7 64-bit.
 
As for the Black Hat training, there is a lot of new and updated content for 2010.

  • Coverage of 64-bit operating systems
  • New section on malware covering different malware techniques and how they stand out in memory
  • Four new case studies ranging from real Advanced Persistent Threat (APT) incidents, to spear phishing attacks, and everything in between
  • Student receive early access Memoryze and Audit Viewer for Windows 7 64-bit
  • Students receive the only free tool to analyze Windows Vista
  • Students receive the only free tool to analyze Windows 2003 64-bit
  • Better data collection to help identify processes and drivers as malicious or not
  • Added the Malware Rating Index (MRI), which helps automatically identify many malware behaviors discussed in the class. Through a simple user interface, students learn how to write rules to identify malware in their own work environments. MRI then uses those rules to score processes as suspicious or not.

 
I would like to thank James Long who pointed out an issue with the batch scripts* and Peter Villadsen who worked so hard to improve the build process and installation for Memoryze. Peter and I would also like to thank all our loyal users. We appreciate all your feedback, and we hope to see you in Las Vegas.

 
* When specifying an output directory from the command line with the batch scripts in Memoryze, the directory must already exist.

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. 06 Jun 10 | Conferences, General, Products | Comments (0)