Puffer Machines, El Al, and Defense in Depth

Airline security is a great case study in large systems security, and specifically the challenges of defense in depth implementation. While the U.S. will rapidly get back to business-as-usual, forgetting the near disaster of a Christmas day airline bombing, other countries have the threat of attack put in their face daily. This isn't something a person wishes the U.S. to experience, but you cannot ignore the ongoing annealing effect this has on the security posture of these foreign communities. It translates into large expenditures of money being applied to security because the threat is real. Contrast the TSA here in the States with El Al in Israel. El Al catches terrorists using multiple layers of security. The first defense is a knowledge of the world they live, the status of their enemies and who is likely to target them at any given time. This means putting intelligence to work and informing different organizations so they can work together. The second layer is a skilled person interrogating passengers. El Al realizes it is not a right to fly, it is a privilege. The screener focuses on the person. El Al respects the power of human threat detection by incorporating the interview into the screening process. The traveler may be asked to produce receipts for the places he reports to have stayed. If the person makes the screener nervous, that person gets set aside for more in depth screening. Simple. This increases the time it takes to check in, but this process has been proven effective. Humans are the best threat detectors in our known universe (seconded by our trusted animal companions). But, here in the States, we are so afraid of being accused of racial profiling and discrimination that TSA is forced to ignore human solutions, and instead relies on mechanical procedures and a compulsive focus on carry-on luggage. The next layer of security is technology based - if a traveler fails to pass the human screener, he or she may be asked to submit to a full body scan, a technology that raises hackles here in the States because of 'privacy' - never mind that it will actually detect plastic explosives taped to the body. The extra cost of sending would-be passengers through a puffer machine is easily shouldered by El Al, because they know it works at detecting explosives. The defense-in-depth goes even further: El Al has special reinforcements in the aircraft fuselage to protect the weakest point against an explosive blast. This is the kind of security that would make me feel safe to fly. All of this is expensive, time consuming and necessary, because it saves lives. The cost of security can't always be measured by money. Some things are more valuable like reputation, goodwill, and peace of mind. The U.S. should take some lessons from this, and start spending smart money on a few key defense-in-depth strategies that work, not only in our airline screening process but in our networks and infrastructure as well. Risk Intelligence is a lot cheaper to implement than we think if we consider the consequences.

Not Kind, Not Gentle. The turn of the decade in security.

The decade in review: The most painful thing we learned is that computer security hasn’t worked. We are, at this very moment, MORE insecure than we were in the year 2000. Billions of dollars were wasted on security technology that isn't working. In the last ten years, true cybercrime was born. Maybe we were just naïve about the coming storm. At the turn of the century, it was hard to get past the romantic idea of a university student hacker who prowled systems harmlessly for fun. Blocking ports and preventing network based buffer overflow attacks seemed so important. None of this technology prevented true criminals from pulling off the biggest heist in computer history – the massive theft of identity and subsequent banking fraud of the last few years. The traditional hacker is dead. Hackers are now called terrorists. The Russian mafia pays developers six figure salaries to write rootkits and malware. Independent researchers can and will sell a reliable working exploit of Internet Explorer for more than $50,000 USD. It began to hurt so bad that even Microsoft had to jump on the secure coding bandwagon, declaring a massive effort to make their code more secure. But this isn’t working either. You see, we are adopting technology at a rate far faster than we can secure it. By the time we have secured something, the landscape has changed and the attackers have moved on. In fact, that is why desktop exploitation has become the dominant attack vector. Over the last few years, malicious documents and media, especially “rich content” that contains embedded logic, parse-able metacode or script, and other logical constructs that can be malformed, emerged as the dominant method of exploitation. The API’s, COM objects, and other hoo-hah piled sky high on your windows workstation is a garden of carnal delights to a skilled attacker. Exploits of this nature have been mostly delivered via Internet Explorer and email. In fact, Internet Explorer is quite possibly the largest software disaster ever. As a software program, it has probably caused over a hundred billion dollars in damages since its release. This isn't about blame - if IE wasn't there, someone else's browser would have been the target. The browser is the portal into the Enterprise, so it's going to be where the bad guys focus. Finally, even before all this was going on, every nation state on the planet was standing in the shadows scared out of their britches. Smart people in high (low?) places could see the writing on the wall. It is TRULY AMAZING that a terrorist hasn’t hacked into the SCADA systems of a municipal power utility, started a cascade failure, and shut down half a state in the dead of winter. It’s because of this that I think [most of] those so-called terrorists aren’t very bright. As we close out the first decade, we must realize we have just entered one of the biggest arms races in the history of warfare. In fact, one can easily say that true cyber warfare was birthed in the last ten years.

So, now my predictions for the next ten years: Very early in the next decade, online identity theft and banking fraud will replace drug trafficking as the dominant criminal problem worldwide. Cyber cartels will make more money annually than drug cartels. Exploitation will continue to be focused on content-based delivery – that is, malicious documents & media. This will be coupled with a massive growth in online social networking. Trust, as a human concept, will be exploited as a means to spread malware throughout social networks via your online digital identity. Again, we will adopt new technology at a rate faster than we can secure it. The largest domain of attack will be software running on cellular phones. The phone will truly evolve into a network terminal – a slightly thicker thin client, loaded with more software in the palm of your hand than you could cram into a Windows 95 box in the year 2000. Yep, you guessed it, another garden of carnal delights – these new platforms will arrive unsecured – the development tools to make software will be insecure, and the people writing the code aren’t going to give a bug’s butt about secure coding practices. So, cyber crime is going to get a lot worse. Meanwhile, we are going to see at least one major SCADA based terrorist attack. We may have no idea that a terrorist did it, because the authorities will never admit it if they can plausibly lie, but it will happen. In fact, it may have already happened. Security spending will shift as well. Starting now, and reaching a heyday in about 6 years, security spending will shift towards host based security solutions. First the government, and then commercial enterprises, will realize that netflows and gateway solutions are not going to stop malware – it’s just too hard to predict what software will do without actually running it. And, online social relationships will be an extension of our professional identity - in other words, when an employee sits down at his workstation, his entire social network sits down with him. Network based security cannot hope to analyze complex documents and media, much less who to trust and when. Because everything will be hosted online, blocking content will effectively break the Internet, and looking inside the content will never happen at the network gateway (don’t invest in companies that think they can solve that problem). Concepts like malware-tolerance will become a hard reality, people will realize you can't keep the bad guys out. While the majority of online crime will continue to be in banking fraud, we are going to see industrial espionage and state-sponsored attacks in the press more than once. And, while banking fraud hurts the individual, the scope and damage of espionage is far far greater. Whether its classified state secrets or the recipe for Coke makes no difference, when the criminals out there figure out the value of information, they WILL steal it. The next ten years are not going to be kind or gentle to the security space. The hardest hit are going to be the biggest in the space – AV vendors are going to take the hardest fall. Their signature based solutions don’t work today, but not everyone knows that yet. But over time, that truth will seep farther into the IT space. So, perhaps my biggest prediction is this – AV will lose their place as the #1 security expenditure in the Enterprise. I’m not sure what will replace it exactly, but I do know that people are going to stop throwing good money after bad.

Blackhat Training is almost here!

I am gearing up for the Blackhat Training session on Monday-Tuesday of next week. We have made room for 30 students. We spent almost four weeks working on materials, remastering the demo and recap videos, and collecting malware samples that illustrated each of the subjects we are presenting. The task was alot harder than I originally expected, especially the collection of malware. I discovered a great trick using our feed processor, which is the clever use of search terms against strings to locate malware that were using specific techniques, keylogging methods, hooking styles, even specific languages. We have a solid methodology we teach behind our Responder product, so I had to find malware that illustrated specific concepts, as opposed to tailoring a training around whatever malware happened to be available. I will try to keep the training as high level as I can, and stay out of disassembly code as much as possible, but as expected there are some key reversing skills that can never be avoided, such as the reconstruction of parameters passed to a call. But, as for arithmetic and hard logic reconstruction, the only exercise where we get into that level of detail will be the one on crypto and stego. We have one coding exercise using the new built-in scripting interface, so thats a short bit of hardcore fun as well. But most of the material is about getting reverse engineering done rapidly, getting what you need, and not bogging down - which is the name of the game.

Reverse engineering process-injecting malware

I posted a video demonstrating some RE work with Responder:

Process Injecting Malware

The RE process starts by searching a livebin's symbols for "remote". A livebin is the in-memory version of an EXE as extracted by Responder. It’s not an executable format, but instead represents the exact layout of the PE formatted file once it loads into virtual memory. Section information does not need to be interpreted to remap the binary in this case, as the OS loader has already done that, including remapping and any other modifications that are made to the layout of code and data at runtime. Many malware programs will be packed on disk, but the livebin will contain large unpacked sections that can be analyzed without the RE having to know anything about the packing methods used, as in effect they are already unpacked for you.

The symbol "CreateRemoteThread" is of interest. For process injection malware you will find this API call almost 100% of the time. There are a few other API calls that are used in conjunction. We drag the symbol to the canvas and examine the region around it. Specifically, we see WriteProcessMemory and VirtualAllocEx - this is a dead giveaway that process injection is in use. Usually a malware will inject a thread that points to the function "LoadLibrary" with the first argument being a path to a DLL that was decompressed to disk - typically in a temporary directory. This is part of the malware's installation system.

In the example, we find that a PID is used to locate a process to inject into. We follow this PID and find the argument is used with LEA. In this case, the LEA is like using the address-of operator in 'c' code.

Imagine the following code:
void *myFunctionPointer;
some_function_call( &myFunctionPointer );


The "some_function_call" is getting a reference to myFunctionPointer, and this means it has the ability to initialize or assign a value into myFunctionPointer. The LEA instruction you see in the video is the assembly version of this same operation. We see this, and follow the function to find a loop where ToolHelpSnapshot32 is used. The toolhelp API set is another very suspicious behavior - if you see this in a potential malware you are very likely dealing with something that enumerates other processes on the system. This is usually a step prior to injection (or an attempt to find a virus scanner or firewall exe and kill it).

There is a string comparison in the process hunting loop - so the malware author is attempting to find a process by name. We follow the arguments back up and see that it's searching for "explorer.exe". The steps shown in the video require moderate-level RE skills, but are not daunting. With a little practice you can follow arguments in and out of function calls without losing your place. The trick is simply to remember that arguments are usually a positive base off of EBP, and local variables are a negative offset. "Parameters are Positive" - use that rule to remember.

The is one exception that is likely to drive you crazy - malware written in Delphi (and there is ALOT of that) usually passes parameters in registers. This can be harder to follow, but again if you label the arguments going into the function you can see these labels at the function boundaries so you don't lose your place.

There are no isolated networks anymore

Highly specialized networks, such as those that control power grids, or esoteric equipment, such as MRI scanners, are not typically considered at risk from Internet attacks. Yet, the recent conficker worm was able to infect these things. It is important to understand that just because hardware seems specialized and distant, it can still be connected to a TCP/IP network. Even if the equipment doesn't offer a convenient web-addressable interface to hack, it can still have a protocol and perform I/O.

Almost all modern but specialized equipment has embedded TCP/IP capabilities and the associated ethernet jack. Web and TCP/IP based technology is a good choice for machine interfacing and configuration. Browsers eliminate the need for specialized client software. Non-specialized programmers can write code that works with a HTTP or HTTPS interface to provide remote configuration capability - this equals lower software development costs.

Specialized equipment often contains a remote data terminal (RDT) which is like an embedded board that contains a mini-OS, likely based on a linux variant or even something like VXWorks. Newly emerging technology, like System on a Chip (SoC) is both inexpensive, and easy to interface to. Even when an RDT type function is not available, these devices may stream large volumes of data outbound over TCP/IP, with the port intended to be used in a specialized LAN configuration for image capturing or other functions (think medical equipment like MRI scanners or X-Ray machines that are interfacing to the PACS network).

The overall point is that these machines are connected to a network that talks TCP/IP. And, following the very nature of TCP/IP, it's easy to make connections that are unintended. So, even though the MRI scanner is not supposed to be connected to the Internet, the imaging workstation will need to talk with the database in Radiology which is then connected to the Hospital Information System (HIS), which is connected to the Internet. You now have an MRI scanner that is attached to machines that can browse the Internet. This is how Conficker got into Heart Monitors running an old unpatched Win2K systems.

Even old equipment falls prey to these unintended exploit paths. Especially for older SCADA equipment, there are tons of devices that will interface good old serial ports to ethernet and TCP/IP pathways. To lower costs, SCADA networks have been refitted with remote access that is routable over ethernet and TCP/IP. The protocols are old and weird, but anyone who does their research can attack them. Even when not directly connected to the Internet (and yes, sometimes they are), devices like power relays are just a few hops away from the Internet-facing gateway. These devices really do control power for small northeastern towns in the dead of winter.

A large amount of the risk here is simply that specialized networks are connected to the Internet via unintended means. These unintended connections between the so-called “protected” networks, and the totally unpatched open equipment is something like a void. It’s not well audited. In some cases, the IT staff may even be discouraged from auditing. In one factory a few years back, the IT staff were forbidden from even running port scans to inventory the network. Apparently doing so once crashed a SCADA controlled machine on the factory floor, so management had forbidden the practice hence. To make things worse, it's incredibly easy to bridge networks without thinking about the security implications. An end user can co-fuse two networks just by plugging in a cable incorrectly. A network admin may not have an extra switch so they use the existing one out of convenience. There are countless scenarios where it's easier to think of specialized systems as non-internet devices, thus not a problem for security.

When dealing with network security, you should always think of every networked device as containing an operating system. It would not harm your security to even think of them as embedded windows operating systems that are vulnerable to conficker worms. You should never think of them as non-internet devices.

Ongoing SCADA Attacks and Network Probes

Consistent and ongoing recon-probes continue to be launched into the US Infrastructure, including government and municipal systems. Boldly stated, all large Enterprises (government and corporate alike) are compromised by some form of malware that is CURRENTLY under C&C from a remote attacker. Malware infections are the tip of the spear - at the other end of an active malware C&C network is a human being or organization with intent and funding.

Recon-probes are malware implants that only scan ports and inventory the resources in the network, then phone home with the data. In many cases, probes are not targeted (not aimed only at your network, but rather like a shotgun approach) - there is an ongoing effort to simply map everything that sits behind the public gateways. In particular, probes have been launched into the US Infrastructure SCADA networks - think power grids and water plants.

Probes will be less complex than a full-blown botnet agent. One component to be on the lookout for is a TCP/IP-only capability - not something that injects into IE or Explorer, but rather a cleaner implant with a port scanning and sniffing capability. These probes will have a C&C backchannel of some kind, but are likely to store their information on disk for a while, as they don't phone home very often. These are forward probes designed to map your network. They may even query the hard-drive serial number via IOCTL's to the NTFS driver, this is for node identification decoupled from the IP address of the host. There will also be a query to see if the box has multiple interfaces.

If you find a probe operation, immediately assume that secondary attack tools have been brought into the network, perhaps in select subnets or on critical gateway machines. Be especially attentive to any sniffing capability on a collision domain near a gateway, or even on the gateway itself. In some cases, secondary capabilities have been dropped that have the ability to shutdown and destroy the computer. If you have captured a probe, immediately check all embedded registry keys and file paths for potential storage locations for secondary equipment.

Rich and Greg in Va. – Ghillie Suits, AR-15’s, Russian Ammunition and Chinese Malware

The morning was spent discussing how lame Conficker.C turned out to be and how it was most likely just barrage jam… meaning a smoke screen diversion to throw off the scent for the “real” slow and low pdf attacks that were slipping into financial institutions in droves. Then on Friday morning HBGary was lucky enough to receive a nice excel spear phishing attack. Unlike most companies we love this stuff. This gives us something to do over the weekend. Greg and I also discussed our new global services offerings which will soon appear on our web site.

After breakfast Greg and I went to an undisclosed location in the Northern Virginia area, got suited up with Ghillie-Suits, AR-15’s, and a 1000 rounds of Wolf Performance Ammunition from Russia. Our mission was to get from point A to point B without getting caught by numerous “individuals”. If we weren’t caught and we made it to point B, we were then to shoot the 500 rounds each at targets from 25 yards up to 100 yards. We had up to 4 hours to cover the terrain, get to Point B, shoot our rounds and get back to point A. without getting caught; again the main point was not getting caught. It was a great! We covered a crazy amount of territory in a short period of time climbing through all kinds of thick brush and most of it was straight up hill to reach point B. At one point we we’re within 50 yards of some of the “individuals” but remained completely still and since we were in our Ghillie-Suits we remained completely still and remained undetected, just like a good rootkit. ;) We ultimately made it to Point B., where we celebrated by drinking some water and dropping our packs to load our rifles. We target practice with Russian ammunition because it’s cheap, pretty reliable and readily available.

As the sun was setting, we had already infected a VM with one of the recent boobytrapped PDF documents. Using a snapshot and Flypaper, we extracted several binaries with Responder and discovered a running botnet out of Russia. The PDF document immediately grabs a malware loader executable from a hacked chinese website, including a flash module. Once the loader executes, the main loader contacts a bot controller located in the ukraine, and the subsequent payload that is downloaded loads a kernel mode rootkit and a usermode module that communicates with a single drop point - a single commercial hacked website to store a drop point, and from this scripted location, data being emailed to a completely different and single hacked email account. The bot control software is something called "JRoger BManager v1.5" and in this case, was operated from a Russian language asset. We made heavy use of NetWitness Informer to capture C&C traffic and compressed downloads of infection modules. We are now tracking this threat to learn more.

Here are some pics:

The Bot Controller

Responder graph of the usermode portion of the malware

NetWitness really boils off the fat. You can slice and dice the data from a packet capture in so many ways. Here are shots:

Overall a good day.