Thursday, December 17, 2020

assume that the threat actor has deployed further persistence mechanisms.

So, anyway, today CERT released an excellent alert about the SolarWinds compromise. It's full of good advice, but my favorite sentence is the one I used as a title.

I will be shocked, if, in the fullness of time, we don't discover that they modified firmware, in order to achieve persistence.

In order to do that, all they need to do is this:

(1) Create a driver capable of reading and writing firmware. This is not easy, but there are examples, such as Chipsec, and don't bother arguing that these perps are not smart enough to do it.

(2) Such a driver would need to be signed, but they already proved they can sign stuff.

(3) Get the driver on the target system. That's what SunBurst (their downloader) can already do.

(4) Modify the right bit of code in the firmware. Remember, there are between 200 and 1,000 compiled C programs, in Windows format, and Bad Guys have been modifying compiled C programs for a long time now. They know how to do that. Oh, and remember that although they are cryptograpically signed, the signature is only checked at flash time.

(5) Remember, it's in the UEFI spec that the firmware can download anything from anywhere using HTTP or FTP, and the firmware has its own network stack.

(6) Once the firmware is modified, SunBurst is perfectly capable of cleaning up such evidense.

My second favorite sentence in the alert is the one about forensically imaging the systems. This is good, but I don't think any forensics kits currently capture firmware.

Folks, everyone needs to start to watch their firmware. You maybe confident that "they" are.

2021 is saying "Hold my beer".

Monday, December 14, 2020

2021 is going to be interesting

So, anyway, in my last post, I opined that 2021 might be saying, "Hold my beer", and this morning we wake up to news of the SolarWinds attack.

Now, so far, there has not been any mention of resultant firmware attacks, but it seems to me that the attackers were sufficently "sophisticated" that they are capable of such attacks.

Systems seem to have been compromised for six to nine months, and that is plenty of time to (1) install a signed firmware driver, (2) modify the firmware, and (3) remove the signed firmware driver.

It might not have happened... but it might have.

The question then becomes... how would you know?

Everyone, from .gov to F500 needs to start to monitor their firmware. It's not part of your average toolkit, but there are options, and I blogged about how to dump your firmware here, and we are happy to help if you need it.

2021 is warming up!

Wednesday, December 9, 2020

2021 is saying, "Hold my beer!"

I have been warning for quite a while, that firmware, particularly UEFI, is the next malware battleground. It is heating up, and everyone needs to start to pay attention.

Consider these items:

One of the RansomWare crews is starting to try to examine, and maybe modify, UEFI

Just to highlight how powerful UEFI is, someone has ported Doom to UEFI. This is pretty awesome, especially if you are a Doom fan, but it sure shows something about UEFI … Doom

The Hacking Team UEFI rootkit seems to have re-surfaced from a nation/state team … Hacking Team

As well as those little itms, having analyzed about 3,000 firmware blobs, here are some of our key findings…

• UEFI firmware contains between 200 and about 1,000 compiled C programs, in Windows format, which is a format well understood by attackers, and defenders, alike.

• approximately half the executables will have signing certificates that are expired. It turns out that certificates are only checked at flash time. What this means is that if something can get write access to the firmware, it could infect, or replace, whatever it likes.

• Nation-state actors have already managed some penetration, with attacks like Shadow Hammer, and LoJax.

• about seven manufacturers have firmware programs that are roughly functionally equivalent to the Lenovo rootkit, from 2015. They are just not as noisy, so they haven’t been noticed.

• out of a random sampling of about 1,500 blobs, 581 had remote update by http or ftp capability, 117 had email capabilities, 1287 had some password reset capability, and 260 contained the word ‘backdoor’

• UEFI has its own network stack, and can download programs, and whole operating systems, from the Internet using http or ftp and some can send email using EHLO

Now, I'm not saying that UEFI is bad. It's the opposite... it's great! It is, however, immensely powerful, and one of the truths of computer security is that functionality (or power) and security tend to exist in an inverse relationship. In other words, the more powerful something is, the less secure it tends to be.

It is clear that our adversaries, from ransomware gangs, to nation/state teams, are attacking the firmware, and it is heating up. Everyone needs to start paying attention. It doesn't matter if your stuff is all in the cloud, because if something bad gets in the firmware, it will be able to find your cloud credentials, and your blockchain private keys, and ... whatever it wants.

Everyone is waiting for 2020 to end, but I reckon 2021 is saying, "Hold my beer, and watch this!"

Wednesday, July 29, 2020

A couple of firmware stats to think about.

So, anyway, just for fun, I grabbed about 1,500 firmware blobs, randomly, from our collection, and ran a few Yara scans over them... just to see... this is what I found.

Total firmware blobs under test: 1520
Number containing overt update capabilities: 581
Number containing overt email capabilities: 117
Number containing some password reset capabilities:1287
Number containing the word 'backdoor': 260

I am still not seeing why firmware should send email, and some even use EHLO, but, oh well...I'm sure there is a good reason.

And, on one hand it's good that firmware has update capabilities, but I still feel nervous about firmware updating over the Internet, using HTTP or FTP. What could go wrong? Oh, that's right ... ShadowHammer already showed what could go wrong.

These updaters, by the way, are the obvious ones... firmware has its own network stack, so there could be other updaters that are a bit obfuscated. No one knows.

And, it's understandable that firmware would need some password reset capabilities, but it's a bit awkward that some contain the word "backdoor".

Now, I have no reason to think any of these are actually malicious, but ... without looking closely, we have no way to be sure. Some could be, and we just don't know, without looking really closely, and I believe that most organizations _are not_ looking at firmware at all, let alone closely. This stuff is immensely powerful, and always remember, functionality and security tend to exist in an inverse relationship.

We may be confident that nation-states are looking hard at firmware attacks, and we may be equally confident that the ransomware players are also trying.

Everyone is using the Hope Method, and this has to change.

If they can get into the firmware of computers, tablets, phones, or IoT, they can persist indefintely, and can either move sideways from there, or simply surveil the network. This would be a Bad Thing(tm).

To keep our critical infrastructure, financial institutions, and medical institutions, safe, everyone in those industries needs to start capturing their firmware, and monitoring it, and if they don't, they're going to regret it.

Stay tuned, folks.

Thursday, April 23, 2020

I might have been wr..wro... wron... can't say the word...

So, anyway, yesterday I smacked poor FaceBook for being creepy, and adding Alt Text to my image, which only showed up because I added it to a Word document, and Word kindly, albeit briefly, showed me the Alt Text.

I was then extra suspicious that something was going on, because I couldn't find the text in the jpg, and figured that it must be compressed, or obfuscated somehow, which lead me to wonder what else might be hidden in the jpg. When you are in my line of business, it's good to be suspicious

But then... a friend commented on my post, saying that he'd had a similar problem with Word a couple of years ago... wait ...what? Word?

Long story made short. Yes, Word adds its own Alt Text to images, and FaceBook was not hiding Alt Text in the images.

Here is Word's Alt Text..

And here is FaceBook's on the same image ...

I was wr... wro... wron.... still can't say the word. :)

The FaceBook Alt Text was just a tag in the html. Yes, it's storing it somewhere, but it's not as creepy as I thought, and Word is doing it too, and probably so is just about any other browser, search engine, word processor, pdf maker... the list goes on.

We can all relax, and go back to worrying about more important things, like firmware issues. Oh... yes... we found some interesting Android firmware stuff yesterday, so stay tuned.

Wednesday, April 22, 2020

That's a bit creepy again, FaceBook!

So, anyway, reasoning that life is too short to be completely serious all the time, I like to tell Dad Jokes. I'm really funny... or at least I think I am.

One of my recent jokes involved a picture, and it went like this...

This is my jar of jars. I call him JarJar. When I shake JarJar, he clinks...

I crack myself up, and as I usually do, I put it on FaceBook.

I am collecting my best (imho) jokes into a document called Grandad Jokes, for my unsuspecting grand kids to read one day, so the easiest way to get the photo onto the right pc was to simply save it from FaceBook.

I then imported it into Word, and this is where it got a bit creepy.

I saw this text appear on the bottom of the imported photo, just for a few seconds...

Wait ... what?.. Alt text? Where did that come from?

It said, "Alt text: A picture containing table, indoor, sitting, food"

Then I remembered reading a few months ago, that FaceBook automatically analysed all photo uploads, so that visually impaired people could have a photo described to them by a robot. While that, on the face of it, sounds very noble, I can't imagine it's terribly effective, because the description just isn't very accurate. I'm not saying FaceBook did anything wrong... it was just hidden and subtle. I may be being cynical, but I suspect that the real benefit is more along the lines of simple statistics for marketing.

Thank goodness that Word showed me, or I wouldn't have known.

One good thing was that I was able to confirm that, by default, FaceBook removes geo location data from the jpg.

A bit more poking around, and I found that I could right click the picture in Word, and one of the options was to edit the Alt Text. That meant that the Alt Text was in the jpg somewhere, but another slightly disquieting thing was that the text was not visible in the jpg, as plain text, so that means it is compressed, or obfuscated somehow, and that leads me to wonder what else might be in there?

I will keep poking.

Chalk up another score for the Privacy Revolution.

Monday, April 20, 2020

Dell agrees that BIOS is the next malware battleground

So, anyway, I recently heard that Dell had released a BIOS testing tool, so I grabbed it and ran it over my trusty Dell Optiplex 7070. The tool was pretty hard to find, but I did find it, and installed it, and it ran, and it pronounced that my BIOS was fine.

That was cool, and expected, but there were a couple of shortcomings.

The first was that it did not tell me that there was an Intel Management Engine upgrade, marked as urgent, and also a BIOS upgrade marked as urgent, which, as a Dell product, I would have thought it should have known about, and told me.

The second was that it doesn't see the sort of things that we see, such as components that seem to have similar functionality to the so-called Lenovo rootkit of 2015.

This makes sense, as this functionality is in there by design, but, in my opinion, is a desirable target for the Bad Guys(tm)

All security pros know that security and functionality tend to exist in an inverse relationship, which is to say that the more functional you make something, the less secure it tends to be.

We think people need to know what (and who) is in their firmware.

To me, the most important aspect of this tool is simply the fact that Dell is acknowledging that the BIOS is the next malware battleground. While poking around for the tool, I also found this report, with the title, "BIOS Security - The Next Frontier For Endpoint Protection".

Folks, all organizations need to start paying attention to what's in their firmware, because it's going to take time to fix.

Tuesday, January 28, 2020

Not cool, Edge.

So, anyway, Windows 10 likes to show me notifications from apps, and stuff, and mostly, that's ok, because I can turn them off from the Chatty Cathy things, and it's handy for the few important ones... and, mostly, they tell you which app it's coming from, so it's easy to turn it off if you don't want it... but ...

There was one that kept coming in, several times a day, and it was annoying, because it would frequently cover up something I was trying to read, or click on... and it wouldn't say what was putting it up.

The only clue I had was that it was from an Asian/English website, devoted to computer security and news, so I thought, "It must be a browser extension."

I have Edge, Chrome and Firefox on this box, so I started searching each of them for extensions.



Then, I got another notification, and no browsers were running.

Hmmmmmmmm again.

I was starting to believe my machine might be compromised, but given that I knew the name of the website, I decided to search the registry for that name, just to see if anything gave me a hint, and sure enough, I found a key associated with MicrosoftEdge\Notifications\Domains. There were about six domains there, including the Chatty Cathy one.

But then I thought, "Wait ... Edge is not running ... how can it be sending me notifications?", so I ran Task Manager, and sure enough, even though the Edge User Interface was not running, Edge _was_ running.

Armed with that knowledge, I was able to go into Edge Advanced Settings, and remove those domains. I don't remember doing it, but I guess I must have clicked on something that allowed those websites to send me notifications. A refresh of the registry showed they were indeed gone, and my laptop is appropriately quiet again, but the disquieting thing is that Edge is still running in the background, and is presumably quietly sharing information, and accepting requests from websites I don't know about.

I don't think there is much I can do about it, although the other browsers don't _seem_ to be running in the background, so I'll see. Maybe this was common knowledge, but I didn't know, so I'm sharing.

At an absolute minimum, this is the Privacy Revolution in action, or mis-action, and to paraphrase Bill Shakespeare and Macbeth, "I hope nothing malicious this way comes."