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  Fileless Malware Detection: A Crash Course
Given you’re here, you’re likely new to this topic, so please be aware in that fileless malware, fileless malware attack, and fileless attack are different words for the same thing. With that clear, let’s jump in!  What is Fileless Malware and How Does It Work? There are many definitions of a fileless malware attack. I like the description from the Poneman Institute:  "A fileless attack is really an attack technique - what we're talking about is a technique - that avoids downloading malicious, executable files, usually to disk, at one stage or another by using exploits, macros, scripts, or legitimate system tools instead. Once compromised, these attacks also abuse legitimate systems and admin tools and processes to gain persistence, elevate privileges, and spread laterally across the network." What's most confusing about these attacks is that they might not be 100% file-free. Typically, different technique types are termed “fileless”, but that doesn't mean the malware or an entire attack campaign won’t include executables at some stage. For example, a traditional phishing attack could have components of a fileless attack in it. Instead of opening the file, clicking on a link and it downloading something to your hard drive, malware may just run in your computer’s memory. It’s a phishing attack, but one piece is fileless. That scenario is more common than a completely fileless malware attack where everything is running in memory. More commonly, we're going to see traditional attacks: phishing campaigns, spoofs, Man in the Middles (MiTM), where something in the attack vector includes malicious code that runs in memory. The other point is that you might hear “fileless attacks” referred to as non-malware attacks, memory-based attacks, in-memory attacks, zero footprint attacks, and macro attacks. These are all different flavors of attack techniques. The whole premise behind the attack is that it is designed to evade protection by traditional file-based or signature-based tools. So any technique designed to try to circumvent or evade detection by those tools really falls into the fileless attack category. Just to get a picture of some of those techniques, in the picture below on the left there are some example delivery methods we see for fileless types of attacks. As we know, phishing and social engineering remain tactics that work for attackers. This nice diagram from Microsoft that shows a full taxonomy of fileless threats. The diagram shows the breadth of different types of techniques and different types of tools, tactics, and procedures that malicious attackers are using to launch attacks. There has been an increase in these attacks. McAfee puts it at 432% growth year over year in Powershell malware that they've witnessed. And SentinelOne found a 94% increase in just the first half of 2018. We're seeing these attack methods persist because they are effective. Attackers are also looking for ways to infiltrate that don't require some kind of vulnerability exploit, to evade detection. Trusted Admin Tools Leveraged for Fileless Attacks Living off the land is the use of trusted admin tools to conduct malicious activity. It's a way to hide in plain sight. These methods help attackers gain persistence within your environment, elevate privileges, and spread laterally across the network. Commonly, we see these with PowerShell, and WMI. We've also seen some using Visual Basic Scripts and UAC Bypass – where attackers are leveraging trusted tools to perform malicious actions. This is true within Linux and Windows as well. Example of a Fileless Malware Attack: GZipDe Here’s an example of an attack and how, at different stages, we see the use of sanctioned applications or different types of a vector that might not register with a file detection tool. Our AlienVault Labs team wrote about this in a blog post in 2018. The way this attack works is through an email phishing campaign that includes an attachment, such as a normal-looking Word document. Once you open that Word document, there's a malicious macro. Once those macros are enabled, a Visual Basic script executes, which launches a hidden PowerShell task, which then connects to the downloads and runs Metasploit in memory. You see a mix of file and fileless attack throughout the process. At first glance, it looks like a traditional attack. Everyone is familiar with phishing campaigns. Then, as you go through the processes, it runs complete programs or attacks in memory - not writing it to a disk so that an anti-virus can’t see it. It also makes this non-persistent. If an attacker is trying to evade audit and capture at a later point, fileless attacks are great. Have a Suspect Machine? One of the first steps you’ll do to investigate and audit a suspect machine is isolate it and turn it off. Since everything runs in memory in these types of attacks, as soon as you turn a suspect machine off, all evidence of the attack will be gone. There are ways to keep these attacks persistent. You can write cron jobs or tasks to a system from a PowerShell script to attain persistence. However, generally, fileless malware attacks are gone once you reboot the computer. Fileless Malware Detection AlienVault® Open Threat Exchange® (OTX™) is a community of security researchers and practitioners. Individuals contribute information to the community after seeing attacks unfold in their environments, just to help others in the community keep up to date. It’s a great resource for anyone who wants to get an understanding of what’s happening in the wild. I searched OTX™ for a few examples of fileless campaigns that we saw in 2018. This is from a quick search of “fileless”. A perfect example of a fileless campaign is GhostMiner cryptomining. It was first recognized a few hundred days ago in our community. It started out as something you would download to your hard drive. It has morphed over time to using an executable PowerShell evasion framework so that they can execute the program within memory rather than downloading it to your drive. It installs cryptomining software, but in a new way. What does it take to detect and defend and begin to protect yourself against these attacks? They are designed to evade file and signature-based protection tools - traditional anti-virus types of tools. What you need is better visibility on the host and on the endpoint. Some of the ways to detect them include things like looking for processes executing shell commands or suspicious commands executed by listening processes like ElasticSearch. We might see excessive network communications from processes that are somewhat abnormal or anomalous, as well as limited persistence and privilege escalation. We might also see attackers trying to cover their tracks by deleting their bash history or installing malicious Chrome browser extensions. All of these can be indicators that there is some type of fileless malware attack occurring in your environment. You’re going to need to spot anomalous behavior rather than a specific Indicator of Compromise (IoC).  To summarize: Conclusion The growing trend of fileless malware attacks will definitely make your life as a defender more challenging. There are free tools, like OTX, to help you keep up, and other offerings, like USM Anywhere to help quickly detect fileless attacks to prevent damage, even when there aren’t yet signatures or IoCs identified for the morphed version of fileless malware. If you’re curious to explore further, check out the Fileless Attacks webcast by Danielle Russell and Aaron Genereaux where they walk you through actual detection examples.       

Le 2019-02-21


  Securing People
Cyber security has three pillars of people, process, and technology. Enterprises have historically had a skewed focus towards the technology aspect of cyber security - installing another endpoint agent, or deploying another network monitoring device designed to seek out anomalys behaviour. While all these things are well and good, when you look at user awareness plans, and most companies have a once-a-year activity where they go over a few points and hope people remain educated. And as far as processes go … well, it’s unclear how much of a conscious effort is put into developing robust processes for cyber security, particularly in small and medium businesses. If we take an unscientific look at some of the trends over the last couple of years, we can see that attacks coming from non-state adversaries has been changing some of its tactics. It is no longer possible for most attackers to waltz in through the virtual front door of organizations and access their data. Which is why many attackers focus on different areas. Three of the most commonly spotted areas are as follows: Employees Going after employees is a tried and tested method. Be that dropping USB drives marked “HR bonus list” in the car park, or sending targeted phishing emails, these attacks have proven to stand the test of time. Phishing emails have been used in many ransomware infections, as well as Business Email Compromise (BEC) rely on duping users within a company. At the beginning of 2019 it was reported that the Indian unit of an Italian firm was targeted and managed to swindle $18.6m. This trend shows no signs of slowing down as Business email compromise (BEC) fraud attacks soared 58% in the UK during 2018, possibly affecting as many as half a million SMEs, according to Lloyds Bank data. Customers Employees aren’t the only ones targeted by criminals. Customers of companies are also fair game in the eyes of hackers. Phishing attacks are a common avenue, with scammers masquerading as popular brands such as Apple or Amazon, threatening behaviour such as law enforcement or the tax office, or even pulling at emotions such as love and greed. In fact a Netflix phishing scam was so bad, even the FTC issued a statement warning customers about it. But phishing isn’t the only attack avenue against customers. Credential stuffing has also risen in popularity. This is where scammers take the passwords of users that have been disclosed in breaches, and use those credentials against other systems in the hope that users have reused passwords across different services. Third Parties Another avenue attackers target are third parties. This could be any company in the supply chain, or with whom the target has a business relationship with. The infamous Target breach of 2013 was conducted after attackers broke in via a HVAC company.   In a more recent incident, LocalBitcoins was targeted by attackers who were able to compromise the sites forums and redirect users to a phishing site from where they captured users credentials. Recommendations Cyber security is perhaps the most challenging game of whack-a-mole in existence. Where we plug one hole, the attackers move to another, easier to exploit hole. With this, we should look to continually move forward and proactively try and stop attackers new tactics becoming full-fledged epidemics. To do so, enterprises need to have a consistent approach to not just user awareness, but also increase awareness for their customers, and 3rd party partners. The most important things to consider would be: Password reuse Raise awareness of the dangers and risks associated with password reuse. Also provide tools or methods to help eliminate password reuse such as the use of password managers. Clicking on links & opening attachments While users within enterprises are getting some training on the dangers of clicking links or opening email attachments, this should extend to customers too. Establish good practices by avoiding sending links in emails, and asking users to navigate directly to the website to log onto their accounts. Reporting issues Finally, and perhaps most importantly is to have a simple and accessible way for both employees and customers to report any suspicious activity. Or indeed, report that they may have fallen victim to a scam by clicking on a link, opening an attachment, or sending sensitive information to a scammer.       

Le 2019-02-20


  Security Have and Have-Nots
Security Have and Have-Nots Way back in around the 2010 / 2011 timeframe Wendy Nather coined the phrase "The Security Poverty Line" in which she hypothesised that organisations, for one reason or another (usually lack of funds), can't afford to reach an effective level of information security. Nearly a decade on, and while the term has sunk into frequent usage within the information security community, are we any better at solving the issue now that we've identified it? I asked Wendy on her thoughts, to which she said, “I don’t think we’ve even come close to understanding it yet. And I think solving it will take an effort on the level of US health care reform.” It’s a morbid thought, and can leave one with a feeling of helplessness. So, I thought I’d try to scratch beneath the surface to see what we can understand about the security poverty line. Technical Debt The term technical debt has become more prevalent within information security over the years. Whereby a company will accrue technical debt, or information security risk over time due to decisions they've made. For example, if a service is launched before undertaking a full penetration test or code review, it adds to the debt of fixing any subsequent issues in a live environment. Exponential Losses One of the challenges with technical debt is that it doesn’t occur in a linear manner, rather the debt, or fall below the poverty line, occurs at an exponential rate. Speaking to people who run small businesses, things become a bit clearer as to some of the challenges they face. Cybersecurity needs investment in different areas, initially that is to hire expertise, or invest in technologies. Neither of which are necessarily the smallest of investments. But then there are ongoing costs - the cost to maintain security, to undertake ongoing testing. Then, when wanting to do business with larger companies, the smaller company is usually subject to a 3rd party assurance process where they need to demonstrate they meet all the cybersecurity requirements of the larger company, even in instances where the controls may not be directly applicable. Finally, in the event of an incident, a company that has already under-invested in security is faced with loss of business, or even legal action from partners, regulatory fines, as well as the cost of incident recovery and PR management. How Much Information Security is Enough? With such a seemingly endless laundry list of things to consider in the security world, the question on the minds of most businesses is, ‘how much is enough’? Unfortunately, if you’re looking for a hard number, you’ll be disappointed. Because the threats and challenges present in the cyber world represent a moving target. But this doesn’t mean all effort is futile, it’s more a case of looking at the world differently. One way to look at this could be through the lens of finite and infinite games, as coined by James Carse in his 1986 book of the same name. The idea is that there are two kinds of games, finite, and infinite games. Finite games are those which have rules such as number of participants, boundaries, time duration, and so forth. After a certain period of time, a winner is declared in accordance with the agreed upon rules. If you try to look at cyber security as a finite game, you will inevitably pull your hair out in frustration and turn into precisely how urban dictionary describes Infosec. Cyber Security is more of an infinite game - one where there is no set rules or boundaries or even a winner or loser as defined in the classical sense. Rather the purpose of an infinite game is to always be in a position to continue the game. Continuing The Game Asking companies to continue the game when resources are scarce and they’re living on the security poverty line. But once you understand the game, the players, the pieces, and the moves, it becomes easier to plan your strategy. For that, it’s useful to consider the following points. 1. People Having the right people can be the difference between making it or not. It doesn’t necessarily mean hiring an entire security department. Sometimes, all it needs is a consultant to help provide guidance and steer towards best security practices to ensure security is built right from the beginning. 2. Technology IT security technologies have come a long way in the last decade. While the constant news cycle may feel like things are getting worse, we actually see more attacks that focus on attacking humans through phishing, or compromises through third parties. Therefore, it makes sense to invest broadly in technologies that offer a broader set of capabilities. These can be more affordable, not just to buy, but to maintain on an ongoing basis. 3. Outsourcing In today’s age of the cloud and service providers, in many cases it doesn’t make sense to keep everything in-house. Securing the services of a reputable MSSP can take away the need to run your own security operation centre. Or having a PR agency on a retainer can help smooth over any incidents that need reporting. 4. Insurance Finally, where risk can’t be mitigated or accepted, consider transferring it to an insurance provider. Not only can insurance help alleviate the financial cost of a breach, but it can a long way in demonstrating to customers, shareholders, or partners that insurance was part of a broad cyber security plan to keep data secure.       

Le 2019-02-08


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