Command-and-Control Servers: What’s Next?
The command-and-control server is a common attack medium used by cybercriminals and hackers to exploit data and breach security. Also called ‘C&C server’ and ‘C2’, this server has the potential to become an incredibly destructive tool, compromising the system security of distributed information networks. The upsurge of security concerns relating to C&C servers continues to influence our approach towards implementing cybersecurity solutions in smartphones, computers, and IoT devices.
According to security researchers, over 1,100 ransomware types are circulating across the world wide web and actively preying on vulnerable users. Every 14 seconds a new computer becomes victim to these ransomware viruses and this number is anticipated to drop down to 11 seconds by 2021. Each year government agencies and security defense organizations spend millions of dollars in response to cybersecurity and ransomware attacks. In 2019, the U.S government spent $176 million in attempts to rebuild networks, restore data backups, and pay the ransom sum. This cost excludes the economic loss suffered by companies in excess of $7.5 billion in 2019.
Nowadays, it is not hard to identify the telltale signs of command-and-control server attacks, a big clue being the anomalous behavior of system software. For instance:
• A random popup message
• Random extensions
• Unfamiliar plugins
• Compromised speed and functionality
This behavior is widely associated with C&C attacks. But they are not the only concerns users need to worry about. A compromised computer, which is part of a C&C network is central to many illicit operations and functions occurring simultaneously from a remote location. Data theft, system shutdown, and Distributed Denial of Service (DDoS) attacks are some of the major cybercrimes hackers accomplish with the aid of the C&C server.
How Do Command-and-Control Servers Work?
The C&C server is a union of multitudes of compromised computers commonly known as botnets. Trojan horses are often used to infect the target computer and effectively turn it into a zombie in control of the C&C server. However, the botnet is not a single computer but is a network of zombies of bots capable of achieving high-end functionality without the knowledge and consent of the owner. With this degree of functionality, cybercriminals can also send spam and malware to other healthy hosts and computers and gradually work towards the expansion of the botnet. Private computers with weak security solutions are the likely target of cybercriminals and play a key role in disrupting cybersecurity measures.
Understanding Botnet Architecture
To understand the true calamity behind C&Cs, it is essential to understand botnet architecture. Botnets are usually controlled by a single Botmaster commanding its ‘troops’ or bots within a command-and-control server to exploit data and breach security. It is easy to understand the botnet architecture with the example of spamming. Spams are usually easy to identify and are often flagged by the system as they are a part of a massive address blacklist. However, the botnet architecture has a simple solution to this security barricade and holds the potential to sends thousands of spam emails from unique addresses simultaneously. By breaching traditional security boundaries, cybercriminals succeed in penetrating systems through spamming, leaving our default security defense system stranded and helpless.
A botnet uses the same spamming principle to create a massive ‘army of zombies’ or bots designed to steal data and sensitive information. As this army of zombie grows, the cybercriminals are able to make more money by attacking thousands of computers simultaneously.
Botnet architecture is used for more than sending spam emails. The greatest security concern associated with command-and-control servers is the Distributed Denial of Service (DDoS) attack. Cybercriminals use botnets to send an endless stream of dummy requests to jam traffic flow in a targeted web server resulting in a collapse of the workflow. There are no ways to regulate and control these dummy requests and businesses have to cater to the demands of cybercriminals to retain their network stability. These dummy requests also overpower the service needs of real users leaving them unserved.
The adverse impact of DDoS is unimaginable. Business owners cannot conceive the dent such attacks create in the long-term integrity of their business.
System Attacks: How Do They Occur?
There are multiple ways C&C can recruit new bots into their existing botnets to expand their network. What makes these bot networks incredibly complex is the simplicity of recruiting newer zombies to strengthen their network. There are two common ways to recruit computers into Command-and-Control Servers:
• Emails and
• Vulnerability Exploitation.
All it takes to bring a private computer into the control of a botmaster is one malicious email with one malicious code attached to a link or a file. Users are still vulnerable even if they have a strong email defense system and the awareness to avoid such malicious emails.
There are other tools that exploit system vulnerabilities to open the backdoor for these malicious programs and trojan horses to step into a system:
• Browser add-ons
• Extensions and other software
Each of these can be used as a host to infect a private computer and swiftly transform it into a zombie controlled by command-and-control servers.
A new breed of C&C servers is on the offensive, with more advanced and complex attack methodologies involving the use of social media, public cloud services, and innovative resources to smartly evade detection. Cybercriminals are now beginning to limit using visible attack tactics and switching to more subtle and low-key modes of attacks. With the use of advanced automation techniques and machine learning, they can smartly navigate across the threat detection systems and exploit data effortlessly. Security software and IT teams find it increasingly difficult to detect newer forms of discrete attacks.
The advent of cloud computing has also opened doors to endless security exploitation possibilities for these resilient C&C servers. Enterprise data and information is becoming more and more vulnerable with the augmentation of data accessibility. This advocates the need for businesses to deploy innovative security measures to neutralize security concerns associated with botnet and C&C servers. These include the likes of two-factor authentication, application whitelisting, end-to-end encryption, and computer monitoring software. Based on the enterprises’ unique security needs, they can even use a combination of these innovative security solutions to safeguard and protect their data from exploitation.
There is no other data storage alternative that has the potential to provide the same level of data accessibility as the cloud computing solution. That’s the reason there is no way across and it is pivotal to identify and implement robust security solutions to protect data in the cloud from these command-and-control server attacks. It is needed to implement data encryption and protection solution on all possible ends and even on local machines to make sure the adequate data protection is provided without compromising on the privacy standards.
Firewalls and network monitoring have traditionally been used to raise flags when suspicious activity is detected. However, as C&Cs evolve, innovative security solutions (such as cyber-attack maps) are needed to effectively track and detect C&C servers. In addition, businesses need to realize the significance of data practices such as historical data analysis to study past attacks to understand and prevent the C&C attacks of the future.
Deep learning, user-behavior analytics, and hardware authentication are also in the list of top emerging information security technologies presently on the rise. With the help of deep learning, information security professionals are working on designing smarter threat detection software and programs designed to restrict the evasion of cybersecurity attacks. User-behavior analytics is another promising security solution having the potential to identify and isolate attack vectors by analyzing the behavior of users working in an interconnected network. On the other hand, hardware authentication emphasizes integrating security solutions in hardware and memory chips to help augment the standards of online information security by robust authentication measures.