Wednesday, August 29, 2018

_Fourth_ Lenovo Rootkit variant

Hi folks,

As our ROM analysis tools continue to improve, we find more "interesting" things. Today, we seem to have found a fourth Lenovo Rootkit variant.

Admittedly, it might not be. It might be just unfortunately named (NovoSecEngine2), but it does seem to share about 97% of the code of some of the other variants, so it looks pretty suspicious.

If you read my other blogs, you will know that two of the variants had 0 detections, and one had a single detection, and unsurprisingly, this one has 0 out of 57 detects.

Again, it's important to understand that I am not suggesting that Lenovo did anything wrong. I think they were completely innocent, and just trying to make their products more secure, and I must emphasize that there is no reason to think any of these are still in circulation, unless someone hasn't updated their firmware.

It's simply instructive that there seem to be four variants, when everyone thought there was just one.

One wonders what else we will find.

Stay tuned.

Wednesday, August 22, 2018

Instructions on how to dump your firmware

Hi folks,

A number of people have asked me how they can participate in firmware gathering, and the short answer is, "Dump your firmware, and upload it to us, at".

As you might expect, the actual answer is a little longer, so here are the instructions for firmware dumping...

On a Mac running High Sierra, it's easy, because there is a built-in command, eficheck. Here are the steps:

1) Open up a terminal

2) This command saves system's EFI firmware, type:

sudo /usr/libexec/firmwarecheckers/eficheck/eficheck --save -b YourFilenameOfChoice.bin

3) This command overwrites EFI variables portions, scrubbing any privacy-sensitive bits, enabling the image to be shared for analysis, type:

sudo /usr/libexec/firmwarecheckers/eficheck/eficheck --cleanup -b YourFilenameOfChoice.bin

4) upload firmware.bin to

Windows is trickier. There are a number of ways, but currently, the easiest seems to be these steps:

Either, (a) download your own version of ChipSec from, read the manual, and make your own zips, or (b) Download a version of ChipSec and an EFI shell from my DropBox (my EFI shell is set for an x86 machine)

and unzip each of those into the root of the thumb drive, and then:
(1) Boot your computer into BIOS, and turn off secure boot
(2) Boot into the thumb drive. This should bring up an EFI shell, that looks a lot like old MsDOS, but is neither Dos nor a Linux shell. It brings up a command prompt that says, “Shell>”
(5) You need to get into the root directory of the thumb drive, by typing FS0:
(I have seen machines where the thumb drive came up as FS1:, and even FS2:, but generally, it’s FS0:)
(6) You should then be able to do a Dir or LS, and see the Chipsec directory, and an EFI directory.
(7) Change directory to chipsec ... cd \chipsec
(8) type: python spi dump filename.bin
(9) type: exit

That should allow you to boot back into BIOS, and turn secure boot back on, and then boot to your OS, and upload the captured file to

Be sure to put your email into the webpage, because some analyses take a while, and your email will allow us to send it to you, when it is complete.

Thanks in advance for your help

Monday, August 20, 2018

Three Lenovo "Rootkit" versions?

Hi folks, In 2015, Lenovo was accused of sending out laptops with a "rootkit" in the firmware. Lenovo essentially said, "Ooops... it was meant to be an updater, to help with security. We bought it from a third party, and assumed it was ok." They patched their firmware, and everyone moved on.

Now, I'm not suggesting for even a second that Lenovo did anything intentionally wrong. I think they were completely innocent, and just trying to make their products more secure, but here's where it gets interesting...

To this day, only one out of about sixty anti-malware products recognizes the rootkit as malicious. If you want to check, search VirusTotal for this sha256, d3c154a38823b09edd2e119ecfd8366c2c5e725fda4f744c04e2d26fcc7c5803, and you will see that only Endgame recognizes it.

This particular bit of software identifies itself as "NovoSecEngine2", in the firmware volume, and is 139,512 bytes long. Now that we have been able to analyze a bunch of firmware, we have found two other executables identifying themselves as NovoSecEngine and NovoSecEngine2. NovoSecEngine is 248,832 bytes long, and the second NovoSecEngine2 is 203,712 bytes long.

Guess how many of the sixty anti-malware programs recognize these No one thinks they are variants of the rootkit.

This means that they are either completely different programs, accidentally sharing the rootkit name, or ... no one has analyzed them.

Our analysis of these two programs continues, and we will post more information as we figure it out, but what this probably really means is that no one is looking at the firmware, and everyone is relying on the "Hope and trust" method.

This, in turn, leads one to wonder how many other programs with rootkit capability lurk in our firmware.

Anything in the firmware is invisible to regular anti-malware programs.

Here are some rough stats from our initial research:

Manufacturers analyzed: {'Toshiba', 'Acer', 'Lenovo', 'Asrock', 'Desenvolvida por Positivo Informatica SA', 'Razer', 'Clevo', 'American Megatrends Inc./Advantech', 'American Megatrends Inc.', 'LG Electronics', 'Dell', 'ASUSTeK', 'Gygabyte', 'Intel', 'Sony', 'Hewlett-Packard', 'Apple Inc.'}

Total firmware analyzed: 550

Total firmware with portable executables analyzed: 515

Total portable executables analyzed: 131289

Total portable executables triggering one heuristic: 20964

Total portable executables triggering more than one heuristic: 3178

Average portable executables per ROM: 254

Average portable executables triggering heuristic per ROM: 40

Average portable executables triggering more than one heuristic per ROM: 6

Now, just because they are triggering our heuristics, doesn't mean they will definitely be bad. It just means that we think they are worthy of a closer look. We will be perfectly happy if all of them are completely innocent, but having been in the anti-malware business for a long time, we suspect we will find some number of Bad Things(tm).

If anyone wants to help, and can upload a firmware dump to us here, we will gladly take a look at it.

Stay tuned, folks, and keep safe.
*** Update: Just in case it's not clear, I don't think these three are currently around, unless someone hasn't updated their BIOS. I think Lenovo took care of it just fine at the time. The point I am trying to make is that there could be lots of other "backdoors" or "rootkits" in firmware, and no one would know. I'm trying to get more people to pay attention.

Wednesday, August 1, 2018

What's in your firmware, and why should you care?

Hi folks, Today, we have officially launched our new site, and product, This is a place where you can upload a firmware image, and get a report on what's in it.

For example, in my 2017 laptop, I have about 380 Windows PE format executables. This is what's known as the Unified Extensible Firmware Interface, or UEFI, for short. The idea is that this mechanism provides a much more flexible way for manufacturers to add new hardware, rather having to modify handwritten assembler, as with a traditional BIOS. This is Good Thing (tm), but they are compiled C code, and this, in turn, is a format well understood by attackers, and defenders, alike.

Fortunately, these programs are cryptographically signed, and are therefore immune to attack... unless...

(1) You can compromise the Root Of Trust. This is the first part of the chain, and is responsible for checking the crypto sig of everything else. This is really hard, and we don't _think_ anyone has done it yet, but we may be sure they are trying, or,

(2) A stolen certificate might be used to sign malicious code, or,

(3) Something malicious might be installed at the factory. It'd never happen, right? Except it already has, at least once, but that's another story.

Extracting a firmware image is mostly complicated, and is not an end-user play, but if you are a geek, and want to know what's in your firmware, there are a couple of ways to get the image.

On a Mac, running High Sierra, you can simply open a terminal, and type "sudo /usr/libexec/firmwarecheckers/eficheck/eficheck --save -b out.bin", and then upload it to

Any machine running Windows 8 or higher, should be using UEFI, and, for Intel based machines, the best approach at this point, is to use Chipsec, and open source tool found here. This requires reading their manual, but is easy enough once you get the idea.

We will make easier mechanisms available as we build them.

Folks, this is tricky stuff, but we need to pay more attention to it, because anything running in the firmware has complete control over the rest of the computer, and probably cannot be seen by anything running at the operating system level. Anything in the firmware is potentially a rootkit.

As well as your own, or your business, computer, think about critical infrastructure devices, medical devices, automobiles, and all IoT devices. They all have firmware, and no one really knows what's in it.

We need to find out.