Tag: information security

Why so much data?

New Year is coming, and usually, during this period, people assess what they did during the previous year. As a person with skills and experience in the defensive part of cybersecurity, I am always quite sensitive about sharing information, contracts, and legal documents with anyone, including institutions. During the last year on multiple times, I had to present official documents and explanations of why and how I did something. On one of the occurrences, I had to deliver around 20, again 20 papers to prove my right. Some of the documents did not relate to the right I wanted to execute, but the institution tried to enforce on me their policy. The representatives in the office even told me that I should trust the institution and that this was the first time someone asked for their data retention period, how they will assure that they will destroy the documents after that period and why they need the data at all.

During the last year, all of these experiences triggered the following questions in my mind – Is my data safe in any institution? Will it be in a safer place if I take care of my data, but not an institution? Can an ordinary person achieve a better level of security than an institution? 

The diagram shows a standard SSD storage system architecture used in almost all database systems. Because of its unique way of storing information, the standard secure delete procedures do not erase the data securely. Special tools are needed for this action, and we could only hope that the institution SysOps department is qualified enough to erase the information properly

For all of these questions, the answers are usually – it depends on the level of expertise of the defending side. So it largely depends on the professionals the institution hired. To strengthen my statement, I can list several case studies that showed how attackers could penetrate even institutions and leak data:

  • Bank Hack: During a regular penetration testing exercise, a team of white hats managed to penetrate multiple office branches of a substantial French bank. Only in one of the offices did the employees ask the penetration expert to identify himself and ask the headquarters whether they sent anyone.
  • Government Taxes Authorities Hack: A couple of years ago, a hacker managed to leak multiple gigabytes of data from the Bulgarian Taxes Agency. The security hole had been opened for an extended period, reported numerous times, and no one took action to close it.
  • Universities Hack: At the beginning of 2021, multiple US universities, including members of the Ivy League, were hacked, and the personal information and documents of their students, lecturers, and professors were leaked to the public.

In conclusion, I think we could safely assume that taking care of our data is our right and responsibility. I am happy to delegate this responsibility only to legal professionals (lawyers, notaries, and judges). They work with confidential documents every day and know how a data leak can affect people. In any other case, sharing data with 3rd parties must come with at least a declaration for their data retention practices and how they destroy the data (there are security practices for doing that correctly). 

Red team that

Red team exercises and penetration testing became our new reality. Especially with COVID-19 and the additional boost to digital transformation, we are more and more digitally dependant. Many countries have started legally enforcing business and governmental organizations to ensure better their cyber security defenses. And the best way to do that is to have regular penetration testing drills once or twice per year.

However, we should ask ourselves how effective is this practice and whether it provides a good level of security for our data and assets. To do that, let’s analyze what the usual workflow of doing a penetration test is. Every engagement in cybersecurity starts with a legal contract, which defines the rules of engagement. In this legal contract, the defending side, the client, negotiates the regulations with the attacking side, aka the penetration testing company. In the case of 3rd party requirements such as governmental and corporation integrations, the rules are defined by the 3rd party. They can even give you a list of “trusted” penetration testing companies from which you have to choose. For example, when we had to do a security audit for Google and Microsoft to allow our integrations, they provided the list of auditing partners we had to use.

On the diagram, you can see a standard Red Team drill workflow. The rules are usually not set by the attacking team

And here is one of the main problems with penetration testing – there are rules of engagement. In the Real Word scenario, there is no such thing as a set of rules. The dedicated attacker can do whatever is necessary to penetrate your defenses, and he/she will not abide by the law. Comparison to conventional military drills is not practical but could even be harmful to your team’s attitude. It is much better to compare the attacker modus operandi to what guerilla fighters do, such as asymmetric warfare, without rules, requirements, etc. Attackers will do what is necessary to penetrate you no more or less.

The second problem with penetration tests is that the attacking team usually has limited time to penetrate your organization. The whole economy around red teaming is based on projects between two weeks and two months long. After that, the attacking team must go to the next assignment. In comparison, real-world hacker teams are usually part of criminal syndicates, and these criminal syndicates have other sources of income such as human trafficking, prostitution, drugs, and weapons. They can happily try to hack one organization for a year or more, especially if it is a big enough target.

And last, but not least – different motivation. In the red team case, the motivation is to abide by a requirement or by law. It means that the penetration team will ensure that the system passes the requirements and rarely will do more. When we speak about real hacker groups, usually we have a pretty limited set of motivation types – money and personal vendetta. Both of these are much higher on the motivation scale than a simple requirement fulfillment.

In conclusion, penetration testing is a helpful activity; however, it is not a panacea. The results coming from it gives a piece of information for your organization’s current cybersecurity state. Unfortunately, the limited scope of every penetration test will not give you a 100% guarantee that attackers can not destroy your defenses. It is much better to treat the red teaming as part of our cybersecurity strategy and valuable security tools.

Cybersecurity tactics for small teams – Network Security – part 1

Please check the previous part – here.

After we finished our two pieces for physical cybersecurity in this and the next one, we shall discuss how to defend your computer network. For a long time, I wondered whether to start with computer and mobile phone devices security first or start with the network security perimeter. In the end, I decided to follow the standard technical approach a computer hacker will use to penetrate your defenses – intelligence recon, network penetration, and finally, device exploits. In social engineering, the hacker will skip network penetration and directly exploit your devices.

So network security, here we go. 

Computer network protocol design is not with security and privacy in mind. After decades of cybercrimes and research on how to stop them, we finally have a solution for these problems. The zero-trust security model is almost 12 years old, with Google using it since 2009. However, despite the good news, the model has its use mainly in big corporates so far. I firmly believe that small organizations and teams can use this model or parts of it. 

But what is the idea of this approach? It is not something new – you have to understand that you can not trust any data in transit, including your own smartphone or laptop apps. Zero trust dictates that the whole network or application path between your application and the server could be malicious, including all the hardware devices along this path – network routers, switches, servers, laptops, and smartphones. 

Still, despite the zero-trust paradigm, I think that people must make sure that the hardware devices under their control are as secure and patched as possible. I market this work approach because the more layers of security you have, the harder it will be for an attacker to penetrate you. Or in short, zero trust does not invalidate other security practices. It just adds new tools to your defensive cybersecurity toolset.

So let’s start with the different network devices and their attack vectors:


So what is a router? A router’s standard definition is a hardware device, which connects different computer networks and forward packets between them. In the case of your home or office router, this is your home/office network and the Internet. Every network packet going to or from the Internet comes and goes through this router. 

In terms of network security, routers are your first line of protection versus network penetration attempts. Or, in simple words, they are your cyber gateway to cyberspace. Additionally, they offer a different range of services regarding your protection. Such services are Firewalls, Intrusion detection systems, NAT service, Syslog server, and many more. 

It is essential to treat your router as a highly specialized computer system. As a computer system, it inherits some of the security problems your personal computer has. Let me list the different attack vectors, which an attacker can use to penetrate your router.

On the diagram, you can see a standard small office deployment. Both of the firewalls are connected in CARP mode, and they become a virtual router. Usually, every firewall is deployed on a standalone hardware device. 
  • Misconfiguration: Sometimes, routers not come with the best configuration in terms of cybersecurity. For example, enabled remote access functionality can be pretty helpful for system administrators, but at the same time, it exposes your router to attackers.
  • Outdated software: Usually, home routers run on quite obsolete software. It is rare, a home user to upgrade the software version of their router. Unfortunately, this leads to systems without proper security patches and gives the attackers an excellent opportunity for hacking the router.
  • Exposed services: Most of the modern routers support additional services such as VPN and IPSec servers. It is essential to understand that every exposed service can be an attack vector for our attacker. In the case of VPN, this is usually not true, but there are exceptions.


Next in line is the network switch. By definition, a network switch is a network device, which connects different network devices into a local computer network by using packet switching to forward and receive data to the destination device. The network switch learns the identities of connected devices and then only delivers data to the port connected to the device to which it is addressed.

In other words, think about the router device as a controller of the local network and about the switch device as an intelligent extender of a local network segment. Still, every switch is a highly specialized computer system, and it inherits the cybersecurity problems other computer systems have. Let me list them.

Most modern companies use cloud providers for their services and do not waste their time deploying hardware. However, the bigger your become, the more hardware you have to set up because it becomes cheaper for you. However, the same principles for cybersecurity apply both to your home office and a multi-national corporation.
  • Network Flood: A malicious actor can try flooding the local network with packets and making it not responsible. Usually, this happens with older switches. Most of the modern ones have protection in place.
  • VLAN sniffing: Most modern switches support network isolation by tagging the packets. This way, different computers in your local networks can not listen to packets living in other virtual networks. Still, if the switch tagging the packets got penetrated, the attacker can listen to all network packets.
  • Remote Access: Newer and more expensive network switches have an entire operating system built inside. It supports remote access features for system administrators and many more. Still, the more one device is intelligent, the bigger the attack surface it has. 

Next part is – here.