Best Free Rootkit Scanner and Remover

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Introduction

Hello Gizmo’s readers!

My co-worker John C from our east coast office came across a page on Malwarebytes' forums and thought I would share since we are putting together our tools for threat removal. The use of italics is my clumsy way of differentiating what I'm writing to Gizmo's readers and what I published to colleagues. Here is the page Malware Removal Guides and Self Help Guides [5].

If you read the first post it refers to Chameleon. This is a tool within Malwarebytes that can find and stop running processes form malware and is very useful on fake alert threats. Chameleon is in a sub folder within the Malwarebytes' main folder.

Below are my testing results that I published to my colleagues with some edits in order to present this to you in an easier to understand language. We are all IT folk so I tend to write to them differently than I would write to Gizmo's readers. Below I speak about System Check which is a rather nasty fake alert. In my next upcoming post I am going to present some methods for removal of these threats along with reviews of Rootkit Scanners. It has been very busy at work and I perform testing in my spare time, of which there has been very little. But I wanted to share this with you so you can add Chameleon to your USB stick.

Below, MBAM is short for Malwarebytes' Anti-Malware. And Rkill is another tool for stopping processes which I will comment on later. The next two paragraphs are from my letter to co-workers:

I tested Chameleon on System Check which is worse than most of the fake alerts in that it hides, everything. I stepped through the instructions listed in the first post of the link provided. I clicked the first box and it opened a small DOS window and then proceeds to kill processes and then update and run MBAM. All of this worked great, and had an unexpected side effect. When it killed the process I think it also killed the ability of this ‘New and Improved’ System Check from deactivating your partitions. I rebooted and came right back into Windows albeit with a black desktop and everything hidden, but it booted!! (But keep in mind, I ran this right after infection, your user will have rebooted probably. More on this below.) I didn’t clean it when MBAM ran this first time because John found that you can run Chameleon as a standalone from your USB stick, and I wanted to test. Sure enough, I copied the whole Chameleon folder over and ran the file from there. Chameleon worked just as it did before, perfect.

So this will be a permanent addition to my USB stick. This will give us the ability to stop the processes fake alerts are running right from your USB and then be able to install and run MBAM without it being compromised. Rkill works much the same way, but is a bit dicey when it runs. In order to shutdown what’s running it will actually rename files. This can be bad however because now MBAM or whatever is being used may not find the renamed file. I would always note the path from Rkill and rename it back to original so MBAM could find it.

I have other news I wanted to share with you about a tool I'm building that will reverse the damage done by the these fake alerts like System Check I refer to above, when they hide all of your menus and folders. I had posted it here but it was too lengthy. I will post a link to it so that you can read it at your leisure. Until than please check out Chameleon as it will be a good addition to any USB stick.

Discussion

There are a lot of anti-rootkit programs available, a lot of this software is very advanced and requires an experienced and technical minded user who is familiar with computers and operating systems. However, there are a couple of options that do not require much technical ability and are also very effective.

[6]The new Top pick is Kaspersky TDSSKiller. It has an easy to use GUI, fast scan times, great detection rate and is user friendly. TDSS Killer managed to detect and remove all modern rootkits tested (TDSS, Zeus, TDLV4, etc). The only down side is TDSS Killer seems to have a narrow range of the rootkits it detects but hopefully more types will be added over time. If more strains are added this may become the definitive tool for removal of rootkits. In my testing what it’s designed to scan for it finds every time and removes it easily and positively. The positives far outweigh the negatives on this one. TDSS Killer also includes 64 bit functionality which is a huge plus.

[7] [8]I have two top choices for all the experienced and technical users GMER and RootRepeal [9]. These are very popular applications, but it takes someone pretty knowledgeable about computer systems to be able to interpret the results. You can find a lot of documentation on both programs but if you are the type of person (like me) who likes to click the scan button and simply wait for the results, you would be better served with TDSS Killer.

For the average user I cannot recommend either of these as without comprehensive computer knowledge the results would be very hard to interpret. I even have a hard time understanding the data. In my work I usually have no time to refer to the documentation and must move quickly to restore a computer to working condition. However, if a particularly difficult infection is present these tools are invaluable because of the wealth of information. I prefer GMER as I find the initial scanning process easier to use and it had a better detection rate han RootRepeal.

[10] Avast Anti-Rootkit resembles a command prompt window but is fairly easy to use. It lets you scan your computer and MBR for rootkits and even fixes any issues. Understanding the output from Avast Anti-rootkit may be a little hard for some users but it does the job well. I tested it against TDSS and several other modern rootkits and it found all of them. Removal on the other hand was not as good as some of the other tools. But what it does have is a very useful tool that I personally would not be without; the ability to perform FixMBR right from within Windows. Normally one would have to boot to a Windows XP disc or Windows 7 recovery disc to perform this command but Avast Anti-Rootkit has a built in ‘FixMBR’ button that with one click will write a new Master Boot Record which is often necessary in the removal of rootkits. This is very useful as you may not always have a Windows disc on hand in the field. I keep this on my USB drive at all times.

[11]The next product that I looked at is one that I always keep in my toolkit. Dr.Web CureIt! is not a standalone anti-rootkit tool like the other tools I recommended, rather it is a free malware scanner and removal tool that happens to be pretty effective at removing some rootkits but doesn’t detect the modern threats in my testing. It is always a good idea to have more than one tool capable of removal, so Dr. Web's freeware scanner is a great addition to anybody's arsenal. What I have found useful is the sandbox environment it creates when it’s run. This is good as it stops all processes that some malware may try to run. It is also able to deep scan your drive and you can reboot back into this environment for further scanning and removal.

Other Rootkit Scanners and Removers

[12] Sophos Anti-Rootkit [13] has a small but easy to use interface with no options other than choosing where you want to scan. As it scans it opens up to a slightly larger interface where it lists the results of the scan and gives you information about each result as well as a recommendation for them. Additionally, a small help file is available that explains the program in a little more detail and gives directions on how to use the command line anti-rootkit tool which is also included. This would be a great tool if it was kept up-to-date but in my testing it failed to find or remove any of the modern threats I tested.

[14]F-Secure Blacklight [15] is another great tool for rootkit removal. Unfortunately, support for it ended a couple of years ago. However, you can still download it on the F-Secure web site and it is compatible with Windows Vista and XP.

Still works well for older rootkits but gives "Incompatible" error if ran on Windows 7. Blacklight is also unable to detect most modern rootkits and therefore, I recommend one of the other tools for now.

Prevx Free [16], the free version of Prevx, offers the same class leading real time detection of the full version but unfortunately it doesn't offer much more than this. Prevx Free is only capable of cleaning select infections, such as Adware, the ZEUS banking trojan, and MBR rootkits. When dealing with rootkits detection is definitely very important, so even if you can't clean all infections you might at least be alerted, enabling you to take further action and manually remove the rootkit or seek help in doing so. As hard as it is to detect the newer, ever evolving rootkits and viruses, Prevx can be a very powerful and informative addition to your regular anti-virus software.

Additionally, Prevx Free can run customized scans from the context menu and also gives you the ability to schedule scans. Another plus is that it scans quickly. The free version also offers protection of stored cookies as well as protection for all of your saved credentials. There is also a browser protection component in the free version but it only offers custom protection on only one web site of your choice. It does however, give the full Prevx Safe Online protection, which includes anti-phishing, protection against hijacks, keyloggers, and cookie stealers for a number of popular websites such as PayPal, or Amazon and of course the one website of your choice.

I have included the previous editor’s information above but would note that given the limited functionality of Prevx Free, I mainly use it for detection. Often I need to not only detect but to remove in one scan using one tool.

As I mentioned above I will leave links to the applications mentioned here as they might work for you and be your favorites. I don’t want to discourage the use of any of them but the ones I haven’t had much success with are in the Other Scanners section; so I cannot recommend them. If they work for you that’s great and I would love to hear of your successes in the comments section.

Along with my goal to provide help is also to give you only what I have found that works. I am always open however to learning of new methods and tools. I love tools and am a firm believer that you cannot have too many. In the ever changing world of threat removal we need many tools to detect and remove.