nick ioannou

Security Audit and Compliance

NICK IOANNOU | January 21, 2021

There is a saying, ‘you can fool all the people some of the time and some of the people all the time.’ Given the fact that there is no such thing as 100% security and human nature being trusting, this has been the backbone of many cyber security scams over the past 20 years. Cyber-criminals know that they will always fool some of the people, so have been modifying and reusing tried and tested methods to get us to open malware ridden email attachments and click malicious web links, despite years of security awareness training. If you search for historic security advice from pretty much any year since the internet became mainstream, you will find that most of it can be applied today. Use strong passwords, do not open attachments or click links from unknown sources. All really familiar advice. So, why are people still falling for modified versions of the same tricks and scams that have been running for over a decade or more? Then again, from the cyber-criminal’s perspective, if it isn’t broken, don’t fix it? Instead, they evolve, automate, collaborate and refine what works. Sound advice for any business! It is possible though to be in a position where you can no longer fool people, even some of the time, because it is no longer their decision to make anymore. This can be achieved by letting technology decide whether or not to trust something, sitting in between the user and the internet. Trust becomes key, and many security improvements can be achieved by limiting what is trusted, or more importantly, defining what not to trust or the criteria of what is deemed untrustworthy. This is nothing new, as we have been doing this for years as many systems will not trust anything that is classed as a program or executable, blocking access to exe or bat files. The list of files types that can act as a program in the Microsoft Windows operating system is quite extensive, if you don’t believe me try to memorize this list: app, arj, bas, bat, cgi, chm, cmd, com, cpl, dll, exe, hta, inf, ini, ins, iqy, jar, js, jse, lnk, mht, mhtm, mhtml, msh, msh1, msh2, msh1xml, msh2xml, msi, ocx, pcd, pif, pl, ps1, ps1xml, ps2, ps2xml, psc1, psc2, py, reg, scf, scr, sct, sh, shb, shs, url, vb, vbe, vbs, vbx, ws, wsc, wsf, and wsh. As you can see, it is beyond most people to remember, but easily blocked by technology. We can filter and authenticate email based on domain settings, reputation scores, blacklists, DMARC (Domain-based Message Authentication Reporting and Conformance) or the components of DMARC, the SPF and DKIM protocols. Email can also be filtered at the content level based on keywords in the subject and body text, the presence of tracking pixels, links, attachments, and inappropriate images that are ‘Not Safe For Work’ (NSFW) such as sexually explicit, offensive and extremist content. More advanced systems add attachment virtual sandboxing, or look at the file integrity of attachments, removing additional content that is not part of the core of the document. Others like ‘Linkscan’ technology look at the documents at the end of a link, which may be hiding behind shortened links or multiple hops, following any links in those documents to the ultimate destination of the link and scan for malware. Where we are let down though is in the area of compromised email accounts from people that we have a trust relationship and work with, like our suppliers. These emails easily pass through most email security and spam filters as they originate from a genuine legitimate email account (albeit one now also controlled by a cyber-criminal) and unless there is anything suspicious within the email in the form of a strange attachment or link, they go completely undetected as they are often on an allow list. This explains why Business Email Compromised (BEC) attacks are so incredibly successful, asking for payments for expected invoices to be made into a ‘new’ bank account, or urgent but plausible invoices that need to be paid ASAP. If the cyber-criminals do their homework and copy previous genuine invoice requests, and maybe add in context chat based on previous emails, there is nothing for most systems or people to pick up on. Only internal processes that flag up BACS payments, change of bank of details or alerts to verify or authenticate can help. Just remember to double-check the telephone number in the email signature before you call, in case you are just calling the criminal. Also, follow the process completely, even if the person you were just about to call has just conveniently sent you an SMS text message to confirm, as SMS can be spoofed. Not all compromised email attacks are asking for money though, many are after user credentials, and contain phishing links or links to legitimate online file sharing services, containing files that then link to malicious websites or phishing links to grant permission to open the file. To give you an idea of the lengths cyber-criminals go to, I’ve received emails from a compromised account, containing a legitimate OneDrive link, containing a PDF with a link to an Azure hosted website, that then reached out to a phishing site. In fact, many compromised attacks are not even on email, as social media is increasingly targeted as well as messaging services or even the humble SMS text message via SIM swap fraud or spoofed mobile numbers. As a high percentage of these are received on mobile devices, many of the standard security defences are not in place, compared to desktop computers and laptops. What is available though are password managers as well as two-factor authentication (2FA) and multi-factor authentication (MFA) solutions which will help protect against phishing links, regardless of the device you use, so long as you train everyone in what to look out for and how they can be abused. One area I believe makes even greater strides in protecting users from phishing and malicious links is to implement technology that defines what not to trust based on the age of a web domain and whether it has been seen before and classified. It really does not matter how good a clone a phishing website is for Office 365 or PayPal if you are blocked from visiting it, because the domain is only hours old or has never been seen before. The choice is taken out of your hands, you still clicked on the link, but now you are taken to a holding page that explains why you are not allowed to access that particular web domain. The system I use called Censornet, does not allow my users to visit any links where the domain is less than 24 hours old, but also blocks access to any domains or subdomains that have not been classified because no one within the global ecosystem has attempted to visit them yet. False positives are automatically classified within 24 hours, or can be released by internal IT admins, so the number of incidents rapidly drops over a short period of time. Many phishing or malicious links are created within hours of the emails being sent, so having an effective way of easily blocking them makes sense. There is also the trend for cyber-criminals to take over the website domain hosting cPanels of small businesses, often through phishing, adding new subdomains for phishing and exploit kits, rather than using spoofed domains. I’ve seen many phishing links over the years pointing to an established brand within the subdomain text of a small hotel. Either way, as these links and subdomains are by their very nature unclassified, the protection automatically covers this scenario too. Other technological solutions at the Domain Name System (DNS) level can also help block IP addresses and domains based on global threat intelligence. Some of these are even free for business use, like Quad9.net and because they are at the DNS level, can be applied to routers and other systems that cannot accept third party security solutions. On mobile devices both Quad9 and Cloudflare offer free apps which involve adding a Virtual Private Network (VPN) profile to your device. Users of public Wi-Fi can be made secure via a VPN, though it’s preferable to have a premium VPN solution on all your user’s mobile devices, as these can be centrally managed and can offer DNS protection as well. Further down the chain of events are solutions like privileged admin rights management and application allow lists. Here, malware is stopped once again because it is not on a trusted list, or allowed to have admin rights. There is also the added benefit that users do not need to know any admin account passwords, so as a result cannot be phished for something they do not know the answer to. Ideally, no users are working with full administrator rights in their everyday activities, as this introduces unnecessary security risks, but can often be overlooked due to work pressures and workarounds. Let’s not forget patch management is also key, because it doesn’t matter how good your security solutions are if they can be bypassed because of a gaping hole via an exploit or vulnerability in another piece of software, whether at the operating system or firmware level, or via an individual application. Sure, no system is perfect and remember there is no such thing as 100% security, which is where the Endpoint Detection and Response (EDR) solutions and Security Information and Event Management (SIEM) solutions come into play. These can help minimize the damage through rapid discovery and remediation, hopefully before the cyber-criminals fully achieve their goals. By harnessing the power of technology to protect us, layering solutions to cover the myriad of ways cyber-criminals constantly attempt to deceive us, we can be confident that emotional and psychological techniques and hooks will not affect technological decisions, as it is a binary choice, either yes or no. The more that we can filter out, makes it less likely that the cyber-criminals will still be able to fool some of the people all the time. This allows security awareness training to focus on threats that technology isn’t as good at stopping, like social engineering tricks and scams. The trick is to spend your budget wisely to cover all the bases and not leave any gaps, which is no easy feat in today’s rapidly changing world.